CN107819546B

CN107819546B - Data transmission method, base station and user equipment

Info

Publication number: CN107819546B
Application number: CN201710812863.2A
Authority: CN
Inventors: 张健; 曾清海; 黄曲芳
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2012-11-13
Filing date: 2012-11-13
Publication date: 2023-07-11
Anticipated expiration: 2032-11-13
Also published as: BR112015010763A2; CN104041102A; EP2908570B1; CN107750064B; BR112015010763B1; US20150244429A1; ZA201503592B; RU2622110C2; MX344890B; MX2015006001A; EP2908570A4; US10110282B2; EP2908570A1; RU2015122423A; WO2014075210A1; US20190028151A1; CN107750064A; CN107819546A

Abstract

The embodiment of the invention provides a data transmission method, a base station and user equipment. The method comprises the following steps: the first base station generates a downlink Radio Link Control (RLC) Protocol Data Unit (PDU); the first base station transmits a first part of downlink RLC PDUs to the user equipment UE, and transmits a second part of downlink RLC PDUs to the second base station, so that the second base station transmits the second part of downlink RLC PDUs to the UE. In the embodiment of the invention, the first base station sends a first part of downlink RLC PDU in the downlink RLC PDU to the UE, and the second base station sends a second part of downlink RLC PDU in the downlink RLC PDU to the UE, so that the first base station and the second base station can jointly send data to the UE, thereby improving the peak rate and throughput of the UE.

Description

Data transmission method, base station and user equipment

Technical Field

The present invention relates to the field of communications, and in particular, to a method, a base station and user equipment for transmitting data.

Background

With the respective developments of mobile communication and broadband wireless access technologies, the services of the two technologies are mutually penetrated, so as to meet the requirement of broadband mobile communication and meet the challenge of broadband mobile communication, the third generation partnership project (the 3rd generation partnership project,3GPP) working group puts higher performance requirements on the communication system, for example, higher requirements on peak rate, system bandwidth and the like. To meet these requirements, 3GPP long term evolution advanced (long term evolution advanced, LTE-A) introduced carrier aggregation (Carrier Aggregation, CA).

The CA can acquire a larger bandwidth by aggregating a plurality of continuous or discontinuous component carriers (component carrier, CC), thereby improving the peak data rate and system throughput, while also solving the problem of carrier spectrum discontinuity. A User Equipment (UE) may support multiple CC aggregation in downlink and uplink, and CCs may be located in the same frequency band (band) or different frequency bands. The CCs aggregated by the UE are provided by the same base station, e.g. co-sited CCs provided by the base station or non co-sited CCs provided by the base station and its remote radio heads (Remote Radio Head, RRH) respectively.

The existing LTE-a technology only supports CA provided by the same base station, and CA cannot be performed when CCs of different base stations have a common coverage area, so that UEs in areas commonly covered by CCs of different base stations need to be switched (handover) to cells with better radio conditions in a moving process, and service delay or interruption is caused in the switching process, so that peak rate and throughput are reduced.

Disclosure of Invention

The embodiment of the invention provides a data transmission method, a base station and user equipment, which can improve the peak rate and throughput of UE.

In a first aspect, a method for transmitting data is provided, including: the first base station generates a downlink Radio Link Control (RLC) Protocol Data Unit (PDU); the first base station transmits a first part of downlink RLC PDUs in the downlink RLC PDUs to User Equipment (UE), and transmits a second part of downlink RLC PDUs in the downlink RLC PDUs to a second base station, so that the second base station transmits the second part of downlink RLC PDUs to the UE.

With reference to the first aspect, in a first possible implementation manner, the method further includes: the first base station receives a first portion of uplink RLC PDUs from the UE, and receives a second portion of uplink RLC PDUs from the second base station, from among the uplink RLC PDUs generated by the UE, wherein the second portion of uplink RLC PDUs is received by the second base station from the UE.

With reference to the first aspect, in a second possible implementation manner, the method further includes: the first base station receiving a first RLC status report from the UE; when the first RLC status report indicates that the RLC PDU of the first portion of downlink RLC PDUs needs to be retransmitted, the first base station retransmits the RLC PDU of the first portion of downlink RLC PDUs, which needs to be retransmitted, to the UE; the first base station forwards the first RLC status report to the second base station, where the first RLC status report indicates an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs, or the first base station sends a retransmission message generated by the first base station according to the first RLC status report to the second base station, where the retransmission message indicates an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs.

With reference to the first aspect, in a third possible implementation manner, the method further includes: the first base station receiving a first RLC status report from the second base station, wherein the first RLC status report is received by the second base station from the UE; the first base station determines the RLC PDU which needs to be retransmitted in the first partial downlink RLC PDU according to the first RLC status report; the first base station retransmits RLC PDUs which need to be retransmitted from the first partial downlink RLC PDUs to the UE.

With reference to the first possible implementation manner of the first aspect, in a fourth possible implementation manner, the method further includes: the first base station generates a second RLC status report according to the receiving conditions of the first part of uplink RLC PDU and the second part of uplink RLC PDU, and sends the second RLC status report to the UE; the first base station receives the RLC PDU of the uplink retransmission set determined by the UE according to the second RLC status report, where the uplink retransmission set includes the RLC PDU needing to be retransmitted in the first part of uplink RLC PDU and/or the RLC PDU needing to be retransmitted in the second part of uplink RLC PDU.

With reference to the fourth possible implementation manner of the first aspect, in a fifth possible implementation manner, the receiving, by the first base station, an RLC PDU of an uplink retransmission set determined by the UE according to the second RLC status report includes: the first base station receives RLC PDUs of the uplink retransmission set from the UE; or the first base station receives RLC PDUs of a first uplink retransmission subset from the UE and RLC PDUs of a second uplink retransmission subset from the second base station, wherein the RLC PDUs of the second uplink retransmission subset are received by the second base station from the UE, and the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission subset by the UE; alternatively, the first base station receives RLC PDUs of the uplink retransmission set from the second base station, the RLC PDUs of the uplink retransmission set being received by the second base station from the UE.

In a second aspect, there is provided a method of transmitting data, comprising: the second base station receives a second part of downlink RLC PDU in the downlink radio link control RLC protocol data unit PDU generated by the first base station from the first base station; the second base station transmits the second part of downlink RLC PDU to the user equipment UE.

With reference to the second aspect, in a first possible implementation manner, the method further includes: the second base station receives a second part of uplink RLC PDU from the UE; the second base station transmits the second portion of uplink RLC PDU to the first base station.

With reference to the second aspect, in a second possible implementation manner, the method further includes: the second base station receives a first RLC status report from the first base station, determines an RLC PDU which needs to be retransmitted in the second part of downlink RLC PDUs according to the first RLC status report, and retransmits the RLC PDU which needs to be retransmitted in the second part of downlink RLC PDUs to the UE; or the second base station receives a retransmission message from the first base station, and retransmits the RLC PDU needing retransmission in the second part of downlink RLC PDUs to the UE according to the retransmission message, wherein the first retransmission message indicates the RLC PDU needing retransmission in the second part of downlink RLC PDUs.

With reference to the second aspect, in a third possible implementation manner, the method further includes: the second base station receiving a first RLC status report from the UE; the second base station forwards the first RLC status report to the first base station, so that when the first RLC status report indicates an RLC PDU which needs to be retransmitted in the first part of downlink RLC PDUs, the first base station retransmits the RLC PDU which needs to be retransmitted in the first part of downlink RLC PDUs to the UE; and when the first RLC status report indicates that the RLC PDU which needs to be retransmitted in the second part of downlink RLC PDUs, the second base station retransmits the RLC PDU which needs to be retransmitted in the second part of downlink RLC PDUs to the UE.

With reference to the first possible implementation manner of the second aspect, in a fourth possible implementation manner, the method further includes: the second base station receives the RLC PDU of the uplink retransmission set from the UE, and sends the RLC PDU of the uplink retransmission set to the first base station, where the uplink retransmission set includes RLC PDU that needs to be retransmitted in the first part of uplink RLC PDU and/or RLC PDU that needs to be retransmitted in the second part of uplink RLC PDU; or the second base station receives RLC PDUs of a second uplink retransmission subset from the UE, and transmits RLC PDUs of the second uplink retransmission subset to the first base station, where the second uplink retransmission subset is obtained by dividing the uplink retransmission set by the UE.

In a third aspect, a method of transmitting data is provided, comprising: the user equipment UE receives a first part of downlink RLC PDUs in downlink radio link control RLC protocol data units PDUs generated by a first base station from the first base station, and receives a second part of downlink RLC PDUs in the downlink RLC PDUs from a second base station, wherein the second part of downlink RLC PDUs is received by the second base station from the first base station.

With reference to the third aspect, in a first possible implementation manner, the method further includes: the UE generates an uplink RLC PDU; the UE transmits a first portion of the uplink RLC PDUs to the first base station and transmits a second portion of the uplink RLC PDUs to the second base station.

With reference to the third aspect, in a second possible implementation manner, the method further includes: the UE generates a first RLC status report according to the receiving conditions of the first part of downlink RLC PDU and the second part of downlink RLC PDU, wherein the first RLC status report indicates the RLC PDU needing to be retransmitted in the first part of downlink RLC PDU and/or the RLC PDU needing to be retransmitted in the second part of downlink RLC PDU; the UE sends the first RLC status report to the first base station or the second base station; the UE receives the RLC PDU which needs to be retransmitted in the first part of downlink RLC PDU from the first base station and/or receives the RLC PDU which needs to be retransmitted in the second part of downlink RLC PDU from the second base station.

With reference to the first possible implementation manner of the third aspect, in a fourth possible implementation manner, the method further includes: the UE receiving a second RLC status report from the first base station; the UE determines an uplink retransmission set according to the second RLC status report, wherein the uplink retransmission set comprises RLC PDU needing retransmission in the first part of uplink RLC PDU and/or RLC PDU needing retransmission in the second part of uplink RLC PDU; the UE transmits the RLC PDU of the uplink retransmission set to the first base station, or transmits the RLC PDU of the uplink retransmission set to the second base station, or transmits the RLC PDU of the first uplink retransmission subset to the first base station and transmits the RLC PDU of the second uplink retransmission subset to the second base station, wherein the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission set by the UE.

In a fourth aspect, there is provided a base station comprising: a generating unit, configured to generate a downlink radio link control RLC protocol data unit PDU; a sending unit, configured to send a first part of downlink RLC PDUs in the downlink RLC PDUs to a user equipment UE, and send a second part of downlink RLC PDUs in the downlink RLC PDUs to a second base station, so that the second base station sends the second part of downlink RLC PDUs to the UE.

With reference to the fourth aspect, in a first possible implementation manner, the method further includes: a first receiving unit, configured to receive, from the UE, a first portion of uplink RLC PDUs in the uplink RLC PDUs generated by the UE, and receive, from the second base station, a second portion of uplink RLC PDUs in the uplink RLC PDUs, where the second portion of uplink RLC PDUs is received by the second base station from the UE.

With reference to the fourth aspect, in a second possible implementation manner, the UE further includes a second receiving unit, configured to receive a first RLC status report from the UE; the sending unit is further configured to retransmit the RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs to the UE when the first RLC status report indicates the RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs; the sending unit is further configured to forward the first RLC status report to the second base station, where the first RLC status report indicates an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs, or send a retransmission message generated by the first base station according to the first RLC status report to the second base station, where the retransmission message indicates an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs.

With reference to the fourth aspect, in a third possible implementation manner, the UE further includes a third receiving unit and a first determining unit, where the third receiving unit is configured to receive a first RLC status report from the second base station, and the first RLC status report is received by the second base station from the UE; the first determining unit is configured to determine, according to the first RLC status report, an RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs; the sending unit is further configured to retransmit, to the UE, an RLC PDU that needs to be retransmitted in the first portion of downlink RLC PDUs.

With reference to the first possible implementation manner of the fourth aspect, in a fourth possible implementation manner, the apparatus further includes a fourth receiving unit, where the generating unit is further configured to generate a second RLC status report according to a reception status of the first portion of uplink RLC PDU and the second portion of uplink RLC PDU, and the sending unit is further configured to send the second RLC status report to the UE; the fourth receiving unit is further configured to receive an RLC PDU of an uplink retransmission set determined by the UE according to the second RLC status report, where the uplink retransmission set includes an RLC PDU that needs to be retransmitted in the first portion of uplink RLC PDUs and/or an RLC PDU that needs to be retransmitted in the second portion of uplink RLC PDUs.

With reference to the fourth possible implementation manner of the fourth aspect, in a fifth possible implementation manner, the fourth receiving unit is specifically configured to receive the RLC PDU of the uplink retransmission set from the UE; or receiving RLC PDUs of a first uplink retransmission subset from the UE, and receiving RLC PDUs of a second uplink retransmission subset from the second base station, where the RLC PDUs of the second uplink retransmission subset are received by the second base station from the UE, and the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission subset by the UE; or receiving RLC PDUs of the uplink retransmission set from the second base station, the RLC PDUs of the uplink retransmission set being received by the second base station from the UE.

In a fifth aspect, there is provided a base station comprising: a receiving unit, configured to receive, from a first base station, a second part of downlink RLC PDUs in a downlink radio link control RLC protocol data unit PDU generated by the first base station; and the sending unit is used for sending the second part of downlink RLC PDU to the User Equipment (UE).

With reference to the fifth aspect, in a first possible implementation manner, the receiving unit is further configured to receive, from the UE, a second part of uplink RLC PDUs in the uplink RLC PDUs generated by the UE; the transmitting unit is further configured to transmit the second portion of uplink RLC PDU to the first base station.

With reference to the fifth aspect, in a second possible implementation manner, the radio link control apparatus further includes a first determining unit, where the receiving unit is further configured to receive a first RLC status report from the first base station, where the first determining unit is configured to determine, according to the first RLC status report, an RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs, and where the sending unit is further configured to retransmit, to the UE, the RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs; or the receiving unit is further configured to receive a retransmission message from the first base station, and the sending unit is further configured to retransmit RLC PDUs required to be retransmitted in the second portion of downlink RLC PDUs to the UE according to the retransmission message, where the first retransmission message indicates RLC PDUs required to be retransmitted in the second portion of downlink RLC PDUs.

With reference to the fifth aspect, in a third possible implementation manner, the receiving unit is further configured to receive a first RLC status report from the UE; the sending unit is further configured to forward the first RLC status report to the first base station, where the first base station is configured to retransmit, to the UE, an RLC PDU that needs to be retransmitted from the first portion of downlink RLC PDUs when the first RLC status report indicates that the RLC PDU that needs to be retransmitted from the first portion of downlink RLC PDUs; the sending unit is further configured to retransmit the RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs to the UE when the first RLC status report indicates the RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs.

With reference to the first possible implementation manner of the fifth aspect, in a fourth possible implementation manner, the receiving unit is further configured to receive RLC PDUs of an uplink retransmission set from the UE, and the sending unit is further configured to send RLC PDUs of the uplink retransmission set to the first base station, where the uplink retransmission set includes RLC PDUs requiring retransmission in the first part of uplink RLC PDUs and/or RLC PDUs requiring retransmission in the second part of uplink RLC PDUs; or the receiving unit is further configured to receive RLC PDUs of a second uplink retransmission subset from the UE, where the sending unit is further configured to send RLC PDUs of the second uplink retransmission subset to the first base station, and the second uplink retransmission subset is obtained by dividing the uplink retransmission subset by the UE.

In a sixth aspect, there is provided a user equipment comprising: a receiving unit configured to receive, from a first base station, a first part of downlink RLC PDUs in downlink radio link control RLC protocol data units PDUs generated by the first base station, and receive, from a second base station, a second part of downlink RLC PDUs in the downlink RLC PDUs, where the second part of downlink RLC PDUs is received by the second base station from the first base station; a first generating unit, configured to reassemble the first portion of downlink RLC PDU and the second portion of downlink RLC PDU to form a downlink RLC service data unit SDU.

With reference to the sixth aspect, in a first possible implementation manner, the method further includes a first sending unit; the first generating unit is further configured to generate an uplink RLC PDU; the first transmitting unit is configured to transmit a first portion of the uplink RLC PDUs to the first base station, and transmit a second portion of the uplink RLC PDUs to the second base station.

With reference to the sixth aspect, in a second possible implementation manner, the apparatus further includes a second generating unit and a second sending unit, where the second generating unit is configured to generate a first RLC status report according to receiving conditions of the first part of downlink RLC PDUs and the second part of downlink RLC PDUs, where the first RLC status report indicates an RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs and/or an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs; the second sending unit is configured to send the first RLC status report to the first base station or the second base station; the receiving unit is further configured to receive an RLC PDU that needs to be retransmitted from the first part of downlink RLC PDUs from the first base station and/or receive an RLC PDU that needs to be retransmitted from the second part of downlink RLC PDUs from the second base station.

With reference to the first possible implementation manner of the sixth aspect, in a third possible implementation manner, the method further includes a determining unit and a third transmitting unit, where the receiving unit is further configured to receive a second RLC status report from the first base station; the determining unit is configured to determine, according to the second RLC status report, an uplink retransmission set, where the uplink retransmission set includes an RLC PDU that needs to be retransmitted in the first portion of uplink RLC PDUs and/or an RLC PDU that needs to be retransmitted in the second portion of uplink RLC PDUs; the third sending unit is configured to send RLC PDUs of the uplink retransmission set to the first base station, or send RLC PDUs of the uplink retransmission set to the second base station, or send RLC PDUs of a first uplink retransmission subset to the first base station and send RLC PDUs of a second uplink retransmission subset to the second base station, where the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission set by the UE.

In a seventh aspect, there is provided a base station comprising: a processor for generating a downlink radio link control, RLC, protocol data unit, PDU; and the transmitter is used for transmitting a first part of downlink RLC PDU in the downlink RLC PDU to the User Equipment (UE) and transmitting a second part of downlink RLC PDU in the downlink RLC PDU to the second base station so that the second base station can transmit the second part of downlink RLC PDU to the UE.

With reference to the seventh aspect, in a first possible implementation manner, the method further includes: and a receiver configured to receive, from the UE, a first portion of uplink RLC PDUs in the uplink RLC PDUs generated by the UE, and to receive, from the second base station, a second portion of uplink RLC PDUs in the uplink RLC PDUs, where the second portion of uplink RLC PDUs is received by the second base station from the UE.

With reference to the seventh aspect, in a second possible implementation manner, the apparatus further includes a receiver; a receiver for receiving a first RLC status report from the UE; the transmitter is further configured to retransmit the RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs to the UE when the first RLC status report indicates the RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs; and the transmitter is further configured to forward the first RLC status report to the second base station, where the first RLC status report indicates an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs, or send a retransmission message generated by the base station according to the first RLC status report to the second base station, where the retransmission message indicates an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs.

With reference to the seventh aspect, in a third possible implementation manner, the apparatus further includes a receiver; a receiver for receiving a first RLC status report from the second base station, wherein the first RLC status report is received by the second base station from the UE; the processor is further configured to determine, according to the first RLC status report, an RLC PDU that needs to be retransmitted in the first portion of downlink RLC PDUs; and the transmitter is further used for retransmitting the RLC PDU which needs to be retransmitted in the first part of downlink RLC PDUs to the UE.

With reference to the first possible implementation manner of the seventh aspect, in a fourth possible implementation manner, the processor is further configured to generate a second RLC status report according to a reception status of the first portion of uplink RLC PDU and the second portion of uplink RLC PDU, and the transmitter is further configured to send the second RLC status report to the UE; and the receiver is further configured to receive an RLC PDU of an uplink retransmission set determined by the UE according to the second RLC status report, where the uplink retransmission set includes an RLC PDU that needs to be retransmitted in the first portion of uplink RLC PDUs and/or an RLC PDU that needs to be retransmitted in the second portion of uplink RLC PDUs.

With reference to the fourth possible implementation manner of the seventh aspect, in a fifth possible implementation manner, the receiver is specifically configured to receive the RLC PDU of the uplink retransmission set from the UE; or receiving RLC PDUs of a first uplink retransmission subset from the UE, and receiving RLC PDUs of a second uplink retransmission subset from the second base station, where the RLC PDUs of the second uplink retransmission subset are received by the second base station from the UE, and the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission subset by the UE; or receiving RLC PDUs of the uplink retransmission set from the second base station, the RLC PDUs of the uplink retransmission set being received by the second base station from the UE.

An eighth aspect provides a base station, comprising: a receiver for receiving, from a first base station, a second part of downlink RLC PDUs in a downlink radio link control RLC protocol data unit PDU generated by the first base station; and a transmitter, configured to send the second portion of downlink RLC PDU to the user equipment UE.

With reference to the eighth aspect, in a first possible implementation manner, the receiver is further configured to receive, from the UE, a second part of uplink RLC PDUs in the uplink RLC PDUs generated by the UE; the transmitter is also configured to transmit the second portion of the uplink RLC PDU to the first base station.

With reference to the eighth aspect, in a second possible implementation manner, the apparatus further includes a processor; the receiver is further configured to receive a first RLC status report from the first base station, the processor is configured to determine, according to the first RLC status report, an RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs, and the transmitter is further configured to retransmit, to the UE, the RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs; or the receiver is further configured to receive a retransmission message from the first base station, and the transmitter is further configured to retransmit RLC PDUs requiring retransmission in the second part of downlink RLC PDUs to the UE according to the retransmission message, where the first retransmission message indicates RLC PDUs requiring retransmission in the second part of downlink RLC PDUs.

With reference to the eighth aspect, in a third possible implementation manner, the receiver is further configured to receive a first RLC status report from the UE; the transmitter is further configured to forward the first RLC status report to the first base station, where the first base station is configured to retransmit RLC PDUs that need to be retransmitted in the first portion of downlink RLC PDUs to the UE when the first RLC status report indicates RLC PDUs that need to be retransmitted in the first portion of downlink RLC PDUs; the transmitter is further configured to retransmit the RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs to the UE when the first RLC status report indicates the RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs.

With reference to the first possible implementation manner of the eighth aspect, in a fourth possible implementation manner, the receiver is further configured to receive RLC PDUs of an uplink retransmission set from the UE, and the transmitter is further configured to send RLC PDUs of the uplink retransmission set to the first base station, where the uplink retransmission set includes RLC PDUs requiring retransmission in the first part of uplink RLC PDUs and/or RLC PDUs requiring retransmission in the second part of uplink RLC PDUs; or the receiver is further configured to receive RLC PDUs of a second uplink retransmission subset from the UE, and the transmitter is further configured to send RLC PDUs of the second uplink retransmission subset to the first base station, where the second uplink retransmission subset is obtained by dividing the uplink retransmission set by the UE.

In a ninth aspect, there is provided a user equipment comprising: a receiver for receiving a first portion of downlink RLC PDUs in a downlink radio link control RLC protocol data unit PDU generated by a first base station from the first base station, and receiving a second portion of downlink RLC PDUs in the downlink RLC PDUs from a second base station, wherein the second portion of downlink RLC PDUs is received by the second base station from the first base station; and the processor is used for recombining the first part of downlink RLC PDU and the second part of downlink RLC PDU to form a downlink RLC service data unit SDU.

With reference to the ninth aspect, in a first possible implementation manner, the device further includes a transmitter; the processor is also used for generating uplink RLC PDU; and the transmitter is used for transmitting a first part of uplink RLC PDU in the uplink RLC PDUs to the first base station and transmitting a second part of uplink RLC PDU in the uplink RLC PDUs to the second base station.

With reference to the ninth aspect, in a second possible implementation manner, the device further includes a transmitter; the processor is further configured to generate a first RLC status report according to the receiving conditions of the first portion downlink RLC PDU and the second portion downlink RLC PDU, where the first RLC status report indicates an RLC PDU that needs to be retransmitted in the first portion downlink RLC PDU and/or an RLC PDU that needs to be retransmitted in the second portion downlink RLC PDU; a transmitter for transmitting the first RLC status report to the first base station or the second base station; the receiver is further configured to receive an RLC PDU that needs to be retransmitted from the first portion of downlink RLC PDUs from the first base station and/or receive an RLC PDU that needs to be retransmitted from the second portion of downlink RLC PDUs from the second base station.

With reference to the first possible implementation manner of the ninth aspect, in a third possible implementation manner, the receiver is further configured to receive a second RLC status report from the first base station; the processor is further configured to determine an uplink retransmission set according to the second RLC status report, where the uplink retransmission set includes an RLC PDU that needs to be retransmitted in the first portion of uplink RLC PDUs and/or an RLC PDU that needs to be retransmitted in the second portion of uplink RLC PDUs; and the transmitter is further configured to send RLC PDUs of the uplink retransmission set to the first base station, or send RLC PDUs of the uplink retransmission set to the second base station, or send RLC PDUs of a first uplink retransmission subset to the first base station and RLC PDUs of a second uplink retransmission subset to the second base station, where the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission set by the UE.

In the embodiment of the invention, the first base station sends a first part of downlink RLC PDU in the downlink RLC PDU to the UE, and the second base station sends a second part of downlink RLC PDU in the downlink RLC PDU to the UE, so that the first base station and the second base station can jointly send data to the UE, thereby improving the peak rate and throughput of the UE.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments of the present invention will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort to a person of ordinary skill in the art.

FIG. 1a is a schematic diagram of one example of a scenario in which an embodiment of the present invention may be applied.

FIG. 1b is a schematic diagram of another example of a scenario in which an embodiment of the present invention may be applied.

FIG. 1c is a schematic diagram of another example of a scenario in which an embodiment of the present invention may be applied.

FIG. 1d is a schematic diagram of another example of a scenario in which an embodiment of the present invention may be applied.

Fig. 2a is a schematic flow chart of a method of transmitting data according to an embodiment of the invention.

Fig. 2b is a schematic flow chart of a method of transmitting data according to an embodiment of the invention.

Fig. 3 is a schematic flow chart of a method of transmitting data according to an embodiment of the invention.

Fig. 4 is a schematic flow chart of a method of transmitting data according to an embodiment of the invention.

Fig. 5 is a schematic diagram of a data transmission process according to an embodiment of the present invention.

Fig. 6 is a schematic flow chart of a data splitting configuration process according to an embodiment of the invention.

Fig. 7 is a schematic diagram of a data transmission process according to an embodiment of the present invention.

Fig. 8 is a schematic flow chart of a configuration process of data splitting according to an embodiment of the present invention.

Fig. 9 is a schematic diagram of one example of a control plane protocol stack according to an embodiment of the invention.

Fig. 10 is a schematic diagram of an example of a user plane protocol stack according to an embodiment of the invention.

Fig. 11 is a schematic structural diagram of layer 2 in the protocol stack of the macro base station according to an embodiment of the present invention.

Fig. 12 is a schematic structural diagram of layer 2 in the protocol stack of the micro base station according to an embodiment of the present invention.

Fig. 13 is a schematic structural diagram of layer 2 in a protocol stack of a UE according to an embodiment of the present invention.

Fig. 14 is a schematic flow chart of a process of a method of transmitting data according to an embodiment of the present invention.

Fig. 15 is a schematic flow chart of a downlink data retransmission process according to an embodiment of the present invention.

Fig. 16 is a schematic flow chart of a downlink data retransmission process according to an embodiment of the present invention.

Fig. 17 is a schematic flow chart of a procedure of a method of transmitting data according to an embodiment of the present invention.

Fig. 18 is a schematic flow chart of an uplink data retransmission process according to an embodiment of the present invention.

Fig. 19 is a schematic flow chart of an uplink data retransmission process according to an embodiment of the present invention.

Fig. 20 is a schematic flow chart of an uplink data retransmission process according to an embodiment of the present invention.

Fig. 21 is a schematic flow chart of a procedure of RRC connection re-establishment according to an embodiment of the present invention.

Fig. 22 is a schematic block diagram of a base station according to an embodiment of the present invention.

Fig. 23 is a schematic block diagram of a base station according to an embodiment of the present invention.

Fig. 24 is a schematic block diagram of a UE according to an embodiment of the present invention.

Fig. 25 is a schematic block diagram of a base station according to an embodiment of the present invention.

Fig. 26 is a schematic block diagram of a base station according to an embodiment of the present invention.

Fig. 27 is a schematic block diagram of a UE according to an embodiment of the present invention.

Fig. 28 is a schematic block diagram of a base station according to an embodiment of the present invention.

Fig. 29 is a schematic block diagram of a base station according to an embodiment of the present invention.

Fig. 30 is a schematic block diagram of a UE according to an embodiment of the present invention.

Fig. 31 is a schematic flow chart diagram of a method of cell resource management according to an embodiment of the invention.

Fig. 32 is a schematic flow chart diagram of a method of cell resource management according to an embodiment of the invention.

Fig. 33 is a schematic flow chart diagram of a method of cell resource management according to an embodiment of the invention.

Fig. 34 is a schematic flow chart diagram of a method of cell resource management according to an embodiment of the invention.

Fig. 35 is a schematic flow chart of an uplink power control method according to an embodiment of the present invention.

Fig. 36 is a schematic flow chart diagram of an uplink power control method according to an embodiment of the present invention.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are some, but not all embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.

A scenario in which embodiments of the present invention are applicable will be described in detail with reference to examples. It should be noted that these examples are only intended to assist those skilled in the art in better understanding the embodiments of the present invention and are not intended to limit the scope of the embodiments of the present invention.

Fig. 1a may be one scenario of an LTE-a system. In fig. 1a, a Macro base station (Macro eNB (eNodeB)) 110a may have a CC1 with a frequency f1, a micro base station (pico eNB) 120a may have a CC2 with a frequency f2, and a coverage area of the CC2 may be located within a coverage area of the CC 1. UE 130a may be in the area covered by CC2, i.e., in the common coverage area of CC1 and CC 2. Then, according to the embodiment of the present invention, after the CCs 1 and 2 are CA, the macro base station 110a and the micro base station 120a may jointly transmit data with the UE 130a, so that the UE 130a does not need to switch between the macro base station 110a and the micro base station 120 a.

For example, if UE 130a currently has a radio resource control (Radio Resource Control, RRC) connection with macro base station 110a, CC1 may be the Primary CC (PCC) and CC2 may be the Secondary CC (SCC) when performing aggregation of CC1 and CC2. The PCC may be used for mobility management and the SCC may provide traffic offloading. The macro base station has wide coverage, and can reduce the occurrence of switching situations when being used for mobility management when being used as PCC. If UE 130a currently has an RRC connection with micro base station 120a, CC2 may be considered as the PCC and CC1 may be considered as the SCC when aggregation of CC1 and CC2 is performed.

Fig. 1b may be another scenario of an LTE-a system. In fig. 1b, the macro base station 110b may have a CC1 with a frequency f1 and the micro base station 120b may have a CC2 with a frequency f 2. There is a common coverage area between CC1 and CC2. UE 130b may be located in a common coverage area of CC1 and CC2. In the same way as in fig. 1a, after the CCs 1 and 2 are CA, the macro base station 110b and the micro base station 110b may also jointly transmit data with the UE 130b, and the UE 130b does not need to switch between the macro base station 110b and the micro base station 110 b.

Fig. 1c may be another scenario of an LTE-a system. In fig. 1c, micro base station 110c may have CC1 with frequency f1 and micro base station 120c may have CC2 with frequency f 2. The coverage area of CC2 may be located within the coverage area of CC 1. UE 130c may be in the area covered by CC2, i.e., in the common coverage area of CC1 and CC2. As in fig. 1a, after CA is performed on CC1 and CC2, micro base station 110c and micro base station 110c may also jointly transmit data with UE 130c, without UE 130c having to switch between micro base station 110c and micro base station 110c, according to an embodiment of the present invention.

It should be noted that, although the above-described scenario of fig. 1c describes a scenario of two micro base stations, the embodiment of the present invention may also be applied to a scenario of two macro base stations, that is, a scenario in which the coverage area of one macro base station may be located within the coverage area of another macro base station, and other processes are similar to those described in fig. 1c, so that repetition is avoided.

Fig. 1d may be another scenario of an LTE-a system. In fig. 1d, the micro base station 110d may have a CC1 with a frequency f1, and the micro base station 120d may have a CC2 with a frequency f 2. There is a common coverage area between CC1 and CC2. UE 130d may be located in a common coverage area of CC1 and CC2. As in fig. 1a, after CA is performed on CC1 and CC2, the micro base station 110d and the micro base station 110d may also perform data transmission with the UE 130d together, and the UE 130d does not need to switch between the micro base station 110d and the micro base station 110d according to the embodiment of the present invention.

It should be noted that, although fig. 1d describes a scenario of two micro base stations, the embodiment of the present invention may also be applied to a scenario of two macro base stations, i.e. a scenario in which there is a common coverage area between the two macro base stations. The other processes are similar to the process described in fig. 1d and are not repeated here.

It should be noted that although two CCs are described in fig. 1a to 1d, the embodiment of the present invention may also be applied to a scenario in which two base stations or more than two base stations respectively have multiple CCs with a common coverage area therebetween, and the multiple CCs of the two base stations are different in frequency or have frequency overlapping. For example, two base stations each provide two carriers with frequencies f1 and f2, where the f1 and f2 carriers of the two base stations each have a common coverage area, and the UE may aggregate f1 of the first base station with f2 of the second base station for CA, or aggregate f2 of the first base station with f1 of the second base station for CA. The UE may aggregate f1 of the first base station and f1 of the second base station for CA, which may also be referred to as coordinated multipoint (coordinated multi point, coMP) transmission/reception (transmission/reception), where the first base station and the second base station communicate with the UE by means of coordinated scheduling. The embodiment of the present invention is not limited thereto.

Fig. 2a is a schematic flow chart of a method of transmitting data according to an embodiment of the invention. The method of fig. 2a is performed by a first base station.

210a, the first base station generates a downlink radio link control (Radio Link Control, RLC) protocol data unit (Protocol Data Unit, PDU).

220a, the first base station sends a first part of downlink RLC PDUs in the downlink RLC PDUs to a User Equipment (UE), and sends a second part of downlink RLC PDUs in the downlink RLC PDUs to the second base station, so that the second base station sends the second part of downlink RLC PDUs to the UE.

In the embodiment of the present invention, the first base station may be used as a user plane anchor point (anchor point) and is responsible for splitting downlink data, for example, the first base station may be one of the macro base station 110a and the micro base station 120a in fig. 1a, and the second base station may be the other. The first base station may also be one of the macro base station 110a and the micro base station 120a in fig. 1b, and the second base station may be the other. The first base station may also be one of the micro base station 110c and the micro base station 120c in fig. 1c, and the second base station may be the other. The first base station may also be one of the micro base station 110d and the micro base station 120d in fig. 1d, and the second base station may be the other. The UE may also be referred to as a Mobile Terminal (MT), a Mobile User Equipment (UE), etc., such as a Mobile phone (or "cellular" phone), a computer with a Mobile Terminal, etc.

It should be noted that the first base station may act as a user plane anchor, and its packet data convergence protocol (Packet Data Convergence Protocol, PDCP) layer receives an internet protocol (Internet Protocol, IP) packet from a Serving Gateway (SGW) from an application layer as a PDCP service data unit (Service Data Unit, SDU), and generates a PDCP PDU after processing by the PDCP protocol layer and delivers it to the RLC layer as an RLC SDU. It should be understood that the first base station may separate the first portion of downlink RLC PDU and the second portion of downlink RLC PDU from the generated downlink RLC PDU after generating the downlink RLC PDU from the RLC SDU. In addition, the first base station may divide the RLC SDU into a first portion of RLC SDU and a second portion of RLC SDU, and after generating the downlink RLC PDU, use the RLC PDU corresponding to the first portion of RLC SDU in the downlink RLC PDU as the first portion of downlink RLC PDU, and use the RLC PDU corresponding to the second portion of RLC SDU as the second portion of downlink RLC PDU.

It should be appreciated that the first portion of downlink RLC PDUs may include one or more RLC PDUs, and the second portion of downlink RLC PDUs may also include one or more RLC PDUs.

The first base station sending the first part of downlink RLC PDU to the UE may refer to that the first base station processes each protocol layer of the first part of downlink RLC PDU and sends the first part of downlink RLC PDU to the UE, for example, the first base station may process the first part of downlink RLC PDU through a medium access control (Medium Access Control, MAC) layer and a Physical (PHY) layer and send the first part of downlink RLC PDU to the UE. Similarly, the second base station sending the second part of downlink RLC PDU to the UE may mean that the second base station processes each protocol layer of the second part of downlink RLC PDU and sends the second part of downlink RLC PDU to the UE, for example, the second base station may process the second part of downlink RLC PDU through the MAC layer and the PHY layer and send the second part of downlink RLC PDU to the UE.

In this way, the UE does not need to switch between two base stations, so that service delay or interruption caused by switching can be avoided.

Alternatively, as an embodiment, the first base station may receive a first portion of uplink RLC PDUs in the uplink RLC PDUs generated by the UE from the UE, and receive a second portion of uplink RLC PDUs in the uplink RLC PDUs from the second base station, where the second portion of uplink RLC PDUs is received by the second base station from the UE.

It should be appreciated that the first portion of uplink RLC PDUs may include one or more RLC PDUs and the second portion of uplink RLC PDUs may also include one or more RLC PDUs.

For the uplink direction, the first base station may receive a first portion of uplink RLC PDU from the UE, and receive a second portion of uplink RLC PDU from the second base station, where the second portion of uplink RLC PDU is sent to the second base station by the UE, and the first base station may recombine the two portions of uplink RLC PDU to generate RLC SDUs, sequentially deliver the RLC SDUs to the PDCP layer as PDCP PDUs, and send the PDCP PDUs to the SGW after subsequent processing.

Note that the first base station receiving the first portion of uplink RLC PDU from the UE may mean that the first base station receives the first portion of uplink data packet from the UE, and processes the first portion of uplink data packet through each protocol layer to obtain the first portion of uplink RLC PDU, for example, the first base station may process the first portion of uplink data packet through the PHY layer and the MAC layer to obtain the first portion of uplink RLC PDU. The procedure for the second base station to receive the second portion of the uplink RLC PDU from the UE is similar to that of the first base station, and will not be repeated here.

Alternatively, as another embodiment, for RLC acknowledged mode (Acknowledged Mode, AM), the first base station may receive a first RLC status report from the UE. When the first RLC status report indicates an RLC PDU that needs to be retransmitted in the first portion of downlink RLC PDUs, the first base station may retransmit the RLC PDU that needs to be retransmitted in the first portion of downlink RLC PDUs to the UE. The first base station may forward a first RLC status report to the second base station, where the first RLC status report may be used to indicate an RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs, or the first base station may send a retransmission message generated by the first base station according to the first RLC status report to the second base station, where the retransmission message may indicate an RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs.

And when the UE is indicated to confirm that the receiving of the successful RLC PDU in the first RLC status report, the first base station updates the RLC AM sending window and the corresponding state variables so as to continue to send the new RLC PDU.

The UE may generate a first RLC status report according to the reception status of the first portion of downlink RLC PDU and the second portion of downlink RLC PDU.

The first base station may determine, according to the first RLC status report, whether there is an RLC PDU that needs to be retransmitted in the first portion of downlink RLC PDUs and the second portion of downlink RLC PDUs. When there is an RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs, the first base station may retransmit the RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs to the UE. When there is an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs, the first base station needs to notify the second base station of the RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs. For example, the first base station may forward the first RLC status report to the second base station, or the first base station may generate a retransmission message according to the first RLC status report, and indicate, to the second base station, RLC PDUs that need to be retransmitted in the second portion of downlink RLC PDUs through the retransmission message.

It should be appreciated that in embodiments of the present invention, RLC status report and RLC PDU retransmission related content is applicable only to RLC AM; the procedure regarding RLC PDU generation, transmission and reception is applicable to both RLC AM and RLC unacknowledged modes (Unacknowledged Mode, UM).

Alternatively, as another embodiment, for the RLC AM, the first base station may determine a downlink RLC PDU retransmission set according to the first RLC status report, where the downlink RLC PDU retransmission set may include an RLC PDU requiring retransmission from among RLC PDUs requiring retransmission in the first portion of downlink RLC PDUs and/or an RLC PDU requiring retransmission in the second portion of downlink RLC PDUs. The first base station may divide the downlink RLC PDU retransmission set into a first downlink retransmission subset and a second downlink retransmission subset. The first base station may retransmit RLC PDUs of the first downlink retransmission subset to the UE. The first base station may generate and send a second retransmission message to the second base station, which may indicate a second subset of downlink retransmissions. If one or more RLC PDUs in the second downlink retransmission subset belong to the original first part of downlink RLC PDUs, the second base station does not have the first part of RLC PDUs because the first base station is responsible for the transmission of the first part of downlink RLC PDUs, and therefore, the first base station also needs to send the RLC PDUs to the second base station.

That is, the first base station may re-divide RLC PDUs that need to be retransmitted, determining that one portion is responsible for retransmission by the first base station and another portion is responsible for retransmission by the second base station. In this way, the method can adapt to the real-time wireless resource conditions of the first base station and the second base station and meet the service quality (quality of service, qoS) requirement of the service, thereby improving the retransmission efficiency.

Alternatively, as another embodiment, for RLC AM, the first base station may receive a first RLC status report from the second base station, wherein the first RLC status report is received by the second base station from the UE. The first base station may determine, according to the first RLC status report, an RLC PDU that needs to be retransmitted in the first portion of downlink RLC PDUs. The first base station may retransmit RLC PDUs requiring retransmission from the first portion of downlink RLC PDUs to the UE.

And when the UE is indicated to confirm that the receiving of the successful RLC PDU in the first RLC status report, the first base station updates the RLC AM sending window and the corresponding state variables so as to continue to send the new RLC PDU. Since the UE sends the first RLC status report according to the uplink resource condition, when the first RLC status report is sent by the second base station, the first base station needs to receive the first RLC status report forwarded by the second base station.

For RLC AM, after generating the first RLC status report, the UE may send the first RLC status report to the second base station, which forwards the first RLC status report to the first base station. And the first base station can retransmit the RLC PDU which needs to be retransmitted in the first part of downlink RLC PDUs to the UE according to the first RLC status report.

Alternatively, as another embodiment, for the RLC AM, the first base station may generate the second RLC status report according to the reception conditions of the first part of uplink RLC PDU and the second part of uplink RLC PDU, and send the second RLC status report to the UE. The first base station may receive RLC PDUs of an uplink retransmission set determined by the UE according to the second RLC status report, where the uplink retransmission set may include RLC PDUs required to be retransmitted in the first portion of uplink RLC PDUs and/or RLC PDUs required to be retransmitted in the second portion of uplink RLC PDUs.

Alternatively, as another embodiment, for the RLC AM, the first base station may generate a second RLC status report according to the reception status of the first part of uplink RLC PDU and the second part of uplink RLC PDU, and send the second RLC status report to the second base station, so that the second base station forwards the second RLC status report to the UE. The first base station may receive RLC PDUs of an uplink retransmission set determined by the UE according to the second RLC status report, where the uplink retransmission set may include RLC PDUs required to be retransmitted in the first portion of uplink RLC PDUs and/or RLC PDUs required to be retransmitted in the second portion of uplink RLC PDUs.

When the first base station is heavy in load or poor in radio condition and the second base station is light in load or good in radio condition, the reliability of sending the second RLC status report can be improved by forwarding the second RLC status report to the UE through the second base station.

Alternatively, as another embodiment, for RLC AM, the first base station may receive RLC PDUs of the uplink retransmission set from the UE. Or the first base station may receive RLC PDUs of the first uplink retransmission subset from the UE, and receive RLC PDUs of the second uplink retransmission subset from the second base station, where the second uplink retransmission subset is received by the second base station from the UE, and the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission subset by the UE. Or the first base station may receive RLC PDUs of an uplink retransmission set from the second base station, the RLC PDUs of the uplink retransmission set being received by the second base station from the UE.

For RLC AM, the first base station may generate a second RLC status report according to the reception status of the first part of uplink RLC PDU and the second part of uplink RLC PDU, and send the second RLC status report to the UE. The UE may determine RLC PDUs requiring retransmission according to the second RLC status report, i.e. determine the uplink retransmission set described above.

The first base station may receive all uplink RLC PDUs requiring retransmission, i.e., RLC PDUs of an uplink retransmission set, from the UE. Alternatively, the first base station may receive a portion of the uplink RLC PDUs requiring retransmission, i.e., RLC PDUs of the first uplink retransmission subset, from the UE. The second base station may receive another portion of the uplink RLC PDU to be retransmitted from the UE, and then send the portion of the uplink RLC PDU, i.e., the RLC PDU of the second uplink retransmission subset, to the first base station. Alternatively, the second base station may receive all uplink RLC PDUs requiring retransmission, i.e., RLC PDUs of the uplink retransmission set, from the UE and then send the RLC PDUs to the first base station.

Alternatively, as another embodiment, the first base station may send the first portion of downlink RLC PDU to the UE on a first cell of the first base station and send the second portion of downlink RLC PDU to the second base station, so that the second base station sends the second portion of downlink RLC PDU to the UE on a second cell of the second base station, where the coverage of the first cell and the second cell overlap.

The carrier of the first base station is provided with a first cell, the carrier of the second base station is provided with a second cell, and the UE can be located in the area where the coverage areas of the first cell and the second cell overlap, so after CA is carried out on the carrier of the first base station and the carrier of the second base station, the first base station can send a first part of downlink RLC PDU to the UE through the first cell. The second base station may send a second portion of downlink RLC PDUs to the UE via the second cell.

Alternatively, as another embodiment, the first base station may send a first request message to the second base station, where the first request message may be used to instruct the second base station to configure the second cell for the UE. The first base station may receive a first response message from the second base station, where the first response message carries resource information of the second cell, such as radio resource configuration public information and radio resource configuration private information of the second cell, which is determined by the second base station according to the first request message. The first base station may send an RRC connection reconfiguration (RRCConnectionReconfiguration) message to the UE, the RRC connection reconfiguration message carrying resource information of the second cell. The first base station may be a macro base station.

For example, the first base station may determine the added cell according to a measurement report of the UE or a measurement result of an uplink sounding reference signal (Sounding Reference Signal, SRS), and the measurement report of the UE may include reference signal received power (Reference Signal Received Power, RSRP) measurement results of the current serving cell and neighbor cells. The first base station may also determine an added cell, such as a channel quality indication (Channel Quality Indication, CQI) reported by the UE, based on other measurements. Thus, after determining that the cell needs to be added for the UE for data offloading, the first base station may indicate to the second base station to configure the second cell of the second base station for the UE. After the first base station receives the resource information of the second cell from the second base station, the resource information of the second cell may be notified to the UE through an RRC connection reconfiguration message. In this way, the UE may perform RRC connection reconfiguration according to the resource information of the second cell. In this case, an RRC connection and data radio bearer (Data Radio Bearer, DRB) may already exist between the first cell of the first base station and the UE.

Optionally, as another embodiment, the first request message may be further used to instruct the second base station to establish a DRB for the UE.

For example, the first base station may determine whether the second base station is required to establish the DRB for the UE according to the QoS parameters, traffic volume, throughput, peak rate, and other information of the DRB. In this way, the first base station may carry DRB configuration information in the first request message, and the second base station may establish an RLC entity and a Logical Channel (LCH) corresponding to the DRB according to the DRB configuration information. For example, the DRB configuration information may include at least one of: an evolved radio access bearer (Evolved Radio Access Bearer, E-RAB) identity, E-RAB quality of service (Quality of Service, qoS) parameters, DRB identity, RLC configuration information, logical channel configuration information. In addition, the DRB configuration information may also include other related information. The E-RAB quality of service parameter may be a QoS parameter after the first base station makes a split decision, for example, the first base station may split the guaranteed bit rate (Guaranteed Bit Rate, GBR), the first base station DRB splits 60%, and the second base station splits 40%, and the GBR parameter value sent to the second base station is 40% multiplied by the original GBR parameter value. The E-RAB quality of service parameter may also be an original QoS parameter received by the first base station from the SGW, and the QoS parameter is adjusted by the second base station during scheduling after the first base station and the second base station negotiate a offloading decision. Similarly, the first base station may carry signaling radio bearer (Signaling Radio Bearer, SRB) configuration information in the first request message, and when the first base station is a user plane anchor point, the second base station may establish an RLC entity and LCH corresponding to the SRB according to the SRB configuration information.

Alternatively, as another embodiment, the first base station may receive a second request message from the second base station, and the second request message may be used to instruct the first base station to configure the first cell for the UE. The first base station may determine, according to the second request message, resource information of the first cell, such as radio resource configuration common information and radio resource configuration dedicated information of the first cell. The first base station may send a second response message to the second base station, where the second response message carries the resource information of the first cell, so that the second base station informs the UE of the resource information of the first cell. The first base station may be a micro base station.

Specifically, the first base station may configure the UE with the first cell according to the indication of the second base station. In this case, the second cell of the second base station may already have an RRC connection and DRB with the UE. The first base station can configure the resources of the first cell for the UE according to the second request message, and can inform the second base station of the resource information of the first cell through the second response message, and the second base station informs the UE of the resource information of the first cell, so that the UE can perform connection reconfiguration according to the resource information of the first cell.

Optionally, as another embodiment, the second request message may be further used to instruct the first base station to establish a DRB for the UE. When the first base station is a user plane anchor point, the first base station may establish a packet data convergence protocol (Packet Data Convergence Protocol, PDCP) entity, an RLC entity, and an LCH corresponding to the DRB according to the second request message.

Similarly, the second request message may also be used to instruct the first base station to establish an SRB for the UE. The first base station may establish PDCP entities, RLC entities, and logical channels corresponding to the SRBs according to the second request message.

For RLC AM, the RLC entity may include a transmitting end and a receiving end, and the transmitting end may include at least one of the following functional units: a transmission buffer (transmission buffer), a retransmission buffer (retransmission buffer), a segmentation and concatenation (concatenation) unit, an RLC PDU header information generating unit (add RLC header), an RLC control unit (RLC control) for an automatic retransmission request (Automatic Retransmission Request, ARQ) function, and the like; wherein the RLC control unit may include at least one of the following functions: ARQ sending window control and maintenance, ARQ receiving window control and maintenance, RLC status report sending generation according to receiving end entity receiving condition, and sending end retransmission control according to received RLC status report. The receiving end may comprise at least one of the following functional units: a routing (routing) unit, a reception buffer (reception buffer), a reordering (reordering) function, RLC header information removal (remove RLC header), an SDU reassembly (reassembly) unit, etc.; the routing unit comprises functions of distinguishing RLC PDU and RLC status report; wherein the reordering function is used for reordering RLC PDUs which the MAC layer fails to deliver to the RLC layer in order, and the MAC layer is out of order because the receiving end fails to successfully receive the transport blocks TB in order due to the hybrid automatic repeat request (Hybrid Automatic Repeat Request, HARQ) retransmission. The sender may also support RLC PDU re-segmentation (segmentation).

For RLC unacknowledged mode (Unacknowledged Mode, UM), the RLC entity may be a transmitting entity or a receiving entity, the transmitting entity may include at least one of the following functional units: a transmission buffer, a segmentation and concatenation unit, an RLC PDU header information generation unit, and the like. The receiving entity may comprise at least one of the following functional units: receiving buffer, reordering function, removing RLC header information, SDU reassembly unit, etc.

Alternatively, as another embodiment, the second request message may also be used to indicate that the first base station is responsible for data offloading. The first base station may send a path switch request message to the mobility management entity (Mobility Management Entity, MME) according to the second request message, so that the MME requests to the SGW to switch the data transmission path to the path of the SGW to the first base station according to the path switch request message.

For example, the second base station is a macro base station, the first base station is a micro base station, the macro base station provides wide coverage and mobility management, the micro base station provides hot spot coverage and capacity, and user service data transmission and reception are mainly performed through the micro base station, so that an anchor point can be migrated to the micro base station, and the data transmission efficiency is improved.

The second base station may decide which base station is used as the user plane anchor point according to the status of the communication process, or the second base station negotiates with the first base station to decide which base station is used as the user plane anchor point, for example, the second base station may determine the user plane anchor point according to the split decision or the split ratio. If the first base station occupies a greater split ratio, e.g., 30% split for GBR, 70% split for the second base station, then the second base station may decide to use the first base station as a user plane anchor. If the second base station serves as the user plane anchor point before, then anchor point migration, or Path Switch (Path Switch), is needed, and the corresponding E-RAB is migrated to the interface between the first base station and the SGW. The first base station may send a path switching request message to the MME, and the MME sends a bearer change request message to the SGW, thereby completing switching of the data transmission path. Thus, by anchor point migration, the shunt efficiency can be improved and the delay can be reduced.

For example, the second base station is a macro base station, the first base station is a micro base station, the wireless condition of the UE in the micro base station is good, the load of the micro base station is small, and the micro base station can bear a larger proportion of user service data, so that an anchor point can be migrated to the micro base station, and the data transmission efficiency is improved.

It should be noted that, for the downlink direction, the data amounts of the first portion of downlink RLC PDU and the second portion of downlink RLC PDU may be statically configured or dynamically adjusted. For the uplink direction, the data amounts of the first part of uplink RLC PDU and the second part of uplink RLC PDU may be statically configured or dynamically adjusted.

For example, the first base station may send a capacity allocation request message to the second base station before offloading data, requesting the second base station to prepare or reserve radio resources for sending the second portion of downlink RLC PDUs or receiving the second portion of uplink RLC PDUs. The second base station may reserve radio resources for the second portion of downlink RLC PDUs or the second portion of uplink RLC PDUs in response to the capacity allocation request message of the first base station. Or the second base station may actively send a capacity allocation indication message to the first base station, where the capacity allocation indication message may indicate a capacity or reserved buffer information of the second base station, so that the first base station sends a second part of downlink RLC PDUs corresponding to the capacity or buffer, or the capacity allocation indication message learns that the second base station may be allocated to radio resource information of the UE for sending the second part of uplink RLC PDUs.

In addition, the second base station may send a capacity adjustment indication message to the first base station according to its scheduling capability and/or buffer change condition, and notify the first base station of the capacity reduction or capacity increase information through the capacity adjustment indication message.

Fig. 2b is a schematic flow chart of a method of transmitting data according to an embodiment of the invention. The method of fig. 2b is performed by the first base station.

210b, the first base station receives a first part of uplink RLC PDUs in the uplink RLC PDUs generated by the UE from the UE, and receives a second part of uplink RLC PDUs in the uplink RLC PDUs from the second base station, wherein the second part of uplink RLC PDUs is received from the UE by the second base station.

Alternatively, as an embodiment, the first base station may reassemble the first portion of uplink RLC PDU and the second portion of uplink RLC PDU after receiving the first portion of uplink RLC PDU and the second portion of uplink RLC PDU.

Alternatively, as another embodiment, the first base station may generate the second RLC status report according to the reception status of the first part of uplink RLC PDU and the second part of uplink RLC PDU, and send the second RLC status report to the UE. The first base station may receive RLC PDUs of an uplink retransmission set determined by the UE according to the second RLC status report, where the uplink retransmission set includes RLC PDUs required to be retransmitted in the first portion of uplink RLC PDUs and/or RLC PDUs required to be retransmitted in the second portion of uplink RLC PDUs.

Alternatively, as another embodiment, the first base station may receive RLC PDUs of the uplink retransmission set from the UE. Alternatively, the first base station may receive RLC PDUs of a first uplink retransmission subset from the UE, and receive RLC PDUs of a second uplink retransmission subset from the second base station, where the RLC PDUs of the second uplink retransmission subset are received by the second base station from the UE, and the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission subset by the UE. Alternatively, the first base station may receive RLC PDUs of an uplink retransmission set from the second base station, the RLC PDUs of the uplink retransmission set being received by the second base station from the UE.

In the embodiment of the invention, the first base station receives a first part of uplink RLC PDUs in the uplink RLC PDUs generated by the UE from the UE and receives a second part of uplink RLC PDUs in the uplink RLC PDUs from the second base station, so that the first base station and the second base station can jointly transmit data with the UE, thereby improving the peak rate and throughput of the UE.

Fig. 3 is a schematic flow chart of a method of transmitting data according to an embodiment of the invention. The method of fig. 3 is performed by a second base station.

The second base station receives 310 a second part of downlink RLC PDUs from the first base station, among the downlink RLC PDUs generated by the first base station.

The second base station sends 320 a second portion of the downlink RLC PDU to the UE.

The first base station may be a user plane anchor point, responsible for offloading data. The first base station may send a first portion of the downlink RLC PDUs to the UE and a second portion of the downlink RLC PDUs to the second base station. And transmitting, by the second base station, a second portion of the downlink RLC PDU to the UE. For example, the first base station may be one of the macro base station 110a and the micro base station 120a in fig. 1a, and the second base station may be the other. The first base station may also be one of the macro base station 110a and the micro base station 120a in fig. 1b, and the second base station may be the other.

In the embodiment of the invention, the second base station sends the second part of downlink RLC PDU in the downlink RLC PDU generated by the first base station to the UE, so that the peak rate and throughput of the UE can be improved.

Alternatively, as another embodiment, the second base station may receive a second part of the UE-generated uplink RLC PDUs from the UE. The second base station may send a second portion of the uplink RLC PDU to the first base station.

The second base station receiving the second portion of uplink RLC PDU from the UE may mean that the second base station receives the second portion of uplink data packet from the UE, and processes the second portion of uplink data packet through each protocol layer to obtain the second portion of uplink RLC PDU, for example, the second base station may process the second portion of uplink data packet through the PHY layer and the MAC layer to obtain the second portion of uplink RLC PDU.

Alternatively, as another embodiment, for the RLC AM, the second base station may receive the first RLC status report from the first base station, determine, according to the first RLC status report, an RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs, and retransmit, to the UE, the RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs. Or, the second base station may receive a retransmission message from the first base station, and retransmit RLC PDUs required to be retransmitted in the second part of downlink RLC PDUs to the UE according to the retransmission message, where the retransmission message indicates RLC PDUs required to be retransmitted in the second part of downlink RLC PDUs.

Specifically, for RLC AM, the second base station may retransmit, to the UE, an RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs according to the first RLC status report forwarded by the first base station or a retransmission message generated by the first base station according to the first RLC status report.

Alternatively, as another embodiment, for RLC AM, the second base station may receive a second retransmission message from the first base station, which may indicate the second downlink retransmission subset. The second base station may retransmit RLC PDUs of the second downlink retransmission subset to the UE according to the second retransmission message.

The first base station may determine a downlink RLC PDU retransmission set according to the first RLC status report, where the downlink RLC PDU retransmission set may include an RLC PDU that needs to be retransmitted in the first portion of downlink RLC PDUs and/or an RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs. The first base station may divide the downlink RLC PDU retransmission set into a first downlink retransmission subset and a second downlink retransmission subset. The first base station may retransmit RLC PDUs of the first downlink retransmission subset to the UE, through a second retransmission message, and notify the second base station that the second base station needs RLC PDUs responsible for the retransmission. If one or more RLC PDUs in the second downlink retransmission subset belong to the original first part of downlink RLC PDUs, the second base station does not have the part of RLC PDUs because the first base station is responsible for the transmission of the first part of downlink RLC PDUs, and then the second base station also needs to receive the RLC PDUs from the first base station.

In this way, the method can adapt to the real-time wireless resource conditions of the first base station and the second base station and meet the service quality (quality of service, qoS) requirement of the service, thereby improving the retransmission efficiency.

Alternatively, as another embodiment, for RLC AM, the second base station may receive the first RLC status report from the UE. The second base station may forward the first RLC status report to the first base station, where the first base station is configured to retransmit RLC PDUs that need to be retransmitted from the first portion of downlink RLC PDUs to the UE when the first RLC status report indicates RLC PDUs that need to be retransmitted from the first portion of downlink RLC PDUs. And when the first RLC status report indicates that the RLC PDU of the second part of downlink RLC PDUs needs to be retransmitted, the second base station may retransmit the RLC PDU of the second part of downlink RLC PDUs needs to be retransmitted to the UE.

In addition, the second base station may forward the first RLC status report to the first base station, so that when the first base station determines that the RLC PDU needing to be retransmitted exists in the first part of downlink RLC PDUs according to the first RLC status report, the first base station retransmits the RLC PDU needing to be retransmitted in the first part of downlink RLC PDUs to the UE.

Alternatively, as another embodiment, for RLC AM, the second base station may receive RLC PDUs of an uplink retransmission set from the UE and send RLC PDUs of the uplink retransmission set to the first base station, where the uplink retransmission set may include RLC PDUs requiring retransmission in the first part of uplink RLC PDUs and/or RLC PDUs requiring retransmission in the second part of uplink RLC PDUs. Or the second base station may receive RLC PDUs of a second uplink retransmission subset from the UE, and send RLC PDUs of the second uplink retransmission subset to the first base station, where the second uplink retransmission subset is obtained by dividing the uplink retransmission set by the UE.

For RLC AM, in the uplink direction, the UE may retransmit all uplink RLC PDUs that need to be retransmitted to the second base station, and the second base station sends the uplink RLC PDUs that need to be retransmitted to the first base station. The UE may divide the uplink RLC PDU to be retransmitted into two parts, one part is retransmitted to the first base station, the other part is retransmitted to the second base station, and the second base station transmits the received RLC PDU to the first base station.

Alternatively, as another embodiment, the second base station may send the second part of the downlink RLC PDU to the UE on a second cell of the second base station.

Alternatively, as another embodiment, the second base station may receive a first request message from the first base station, and the first request message may be used to instruct the second base station to configure the second cell for the UE. The second base station may determine resource information of the second cell according to the first request message. The second base station may send a first response message to the first base station, where the first response message carries resource information of the second cell, so that the first base station informs the UE of the resource information of the second cell.

Optionally, as another embodiment, the first request message may be further used to instruct the second base station to establish a DRB for the UE. The second base station may establish RLC entities and logical channels corresponding to the DRBs according to the first request message.

Since the second base station does not act as a user plane anchor point, the PDCP entity may not be established. Alternatively, the second base station may establish the PDCP entity, and may turn off the PDCP entity after the establishment since the function of the PDCP entity is not required.

For RLC AM, the RLC entity may include a transmitting end and a receiving end, and the transmitting end may include at least one of the following functional units: a transmission buffer area and a retransmission buffer area; optionally, the method comprises a segmentation unit and an RLC PDU header information generation unit, which can only support the re-segmentation function of the RLC PDU and generate RLC header information due to re-segmentation; the sending buffer area is used for receiving the RLC PDU sent by the first base station; the retransmission buffer is used for storing RLC PDUs potentially requiring retransmission, for example, after RLC PDUs of the transmission buffer are first transmitted to the UE, the RLC PDUs are shifted into the retransmission buffer. Optionally, the method comprises an RLC control unit, wherein the RLC control unit controls retransmission of RLC PDUs of the second base station according to an RLC status report from the first base station; controlling the retransmission of the RLC PDU of the second base station according to the RLC status report from the UE, and forwarding the complete RLC status report control to the second base station; the RLC control unit does not itself generate RLC status reports and need not maintain ARQ transmission and reception windows. The transmitting end may also only include a transmitting buffer area, which is used for receiving RLC PDU sent by the first base station and forwarding to the UE; the second base station does not need to support RLC PDU retransmission, or the first base station retransmits RLC PDUs requiring retransmission as new RLC PDUs to the transmission buffer of the second base station for forwarding to the UE through the second base station. The receiving end may comprise at least one of the following functional units: a receive buffer; optionally, a reordering function; optionally, a routing function; optionally, an SDU reassembly unit is included, but set to an off state.

For RLC UM, the RLC entity may be a transmitting entity or a receiving entity, and the transmitting entity may include at least one of the following functional units: the transmission buffer, optionally further including a segmentation unit and an RLC PDU header information generating unit, may support only RLC PDU re-segmentation function and generate RLC header information due to re-segmentation. The receiving entity may comprise at least one of the following functional units: a receive buffer, optionally including a reordering function; optionally, an SDU reassembly unit is included, but set to an off state.

Alternatively, as another embodiment, the second base station may send a second request message to the first base station, where the second request message may be used to instruct the first base station to configure the first cell of the first base station for the UE. The second base station receives a second response message from the first base station, wherein the second response message carries the resource information of the first cell determined by the first base station according to the second request message. And the second base station sends an RRC connection reconfiguration message to the UE, wherein the RRC connection reconfiguration message carries the resource information of the first cell.

Optionally, as another embodiment, the second request message may be further used to instruct the first base station to establish a DRB for the UE.

Fig. 4 is a schematic flow chart of a method of transmitting data according to an embodiment of the invention. The method of fig. 4 is performed by a UE, which may be, for example, UE 130a in fig. 1a or 130b in fig. 1 b.

410, the ue receives a first part of downlink RLC PDUs in RLC PDUs generated by the first base station from the first base station, and receives a second part of downlink RLC PDUs in the downlink RLC PDUs from the second base station, wherein the second part of downlink RLC PDUs is received by the second base station from the first base station.

In the embodiment of the invention, the UE receives the first part of downlink RLC PDU from the first base station and the second part of downlink RLC PDU acquired from the first base station by the second base station from the second base station, so that the UE can jointly transmit data with the two base stations, thereby improving the peak rate and throughput of the UE.

In this way, the UE in the coverage area common to the two base stations does not need to switch between the two base stations, so that service delay or interruption caused by switching can be avoided.

Alternatively, as an embodiment, the UE may reassemble the first portion of downlink RLC PDU and the second portion of downlink RLC PDU to form the downlink RLC SDU.

Alternatively, as another embodiment, the UE may generate an uplink RLC PDU. The UE may send a first portion of the uplink RLC PDUs to the first base station and a second portion of the uplink RLC PDUs to the second base station.

The PDCP layer of the UE can receive the IP data packet from the application layer as PDCP SDU, generates PDCP PDU after being processed by the PDCP protocol layer, submits the PDCP PDU to the RLC layer as RLC SDU, and generates the uplink RLC PDU from the RLC SDU.

For the uplink direction, the UE may send a part of RLC PDU to the first base station, send another part of RLC PDU to the second base station, and send the part of RLC PDU to the first base station by the second base station, so that the peak rate and throughput of the UE can be improved.

Note that the UE sending the first portion of uplink RLC PDU to the first base station may refer to that the UE processes each protocol layer of the first portion of uplink RLC PDU and sends the first portion of uplink RLC PDU to the first base station, for example, the UE may process the first portion of uplink RLC PDU through the MAC layer and the PHY layer and sends the first portion of uplink RLC PDU to the first base station. The procedure of the UE transmitting the second portion of the uplink RLC PDU to the second base station is similar, and in order to avoid repetition, details are not repeated here.

Optionally, as another embodiment, the UE generates a first RLC status report according to the receiving conditions of the first part of downlink RLC PDU and the second part of downlink RLC PDU, where the first RLC status report indicates an RLC PDU that needs to be retransmitted in the first part of downlink RLC PDU and/or an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDU. The UE may send a first RLC status report to the first base station or the second base station. The UE may receive RLC PDUs requiring retransmission from the first part of downlink RLC PDUs from the first base station and/or RLC PDUs requiring retransmission from the second part of downlink RLC PDUs from the second base station.

For RLC AM, the UE may generate a first RLC status report according to the reception status of the first part of downlink RLC PDU and the second part of downlink RLC PDU. The UE may send the first RLC status report to the first base station or may send the first RLC status report to the second base station. If there is an RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs, the UE may receive the RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs from the first base station. If there is an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs, the UE may receive the RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs from the second base station.

It should be noted that the UE may also divide the first RLC status report into two segments according to uplink resource conditions, and simultaneously send two segments of the first RLC status report from the first base station and the second base station, where the second base station forwards one segment of the first RLC status report received by itself to the first base station.

Alternatively, as another embodiment, for the RLC AM, the UE generates a first RLC status report according to the reception conditions of the first part of downlink RLC PDU and the second part of downlink RLC PDU, and transmits the first RLC status report to the first base station. The UE may receive RLC PDUs of the first downlink retransmission subset from the first base station, and receive RLC PDUs of the second downlink retransmission subset from the second base station, where the first downlink retransmission subset and the second downlink retransmission subset are obtained by dividing a downlink RLC PDU retransmission set by the first base station, and the downlink RLC PDU retransmission set may be determined by the first base station according to the first RLC status report, and the downlink RLC PDU retransmission set may include RLC PDUs needing to be retransmitted in the first part of downlink RLC PDUs and/or RLC PDUs needing to be retransmitted in the second part of downlink RLC PDUs from the second base station.

Alternatively, as another embodiment, for RLC AM, the UE may receive a second RLC status report from the first base station. The UE may determine, according to the second RLC status report, an uplink retransmission set, where the uplink retransmission set includes RLC PDUs requiring retransmission in the first portion of uplink RLC PDUs and/or RLC PDUs requiring retransmission in the second portion of uplink RLC PDUs. The UE transmits the RLC PDU of the uplink retransmission set to the first base station, or transmits the RLC PDU of the uplink retransmission set to the second base station, or transmits the RLC PDU of the first uplink retransmission subset to the first base station and transmits the RLC PDU of the second uplink retransmission subset to the second base station, wherein the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission set by the UE.

For RLC AM, the UE may determine, according to the second RLC status report, an uplink RLC PDU that needs to be retransmitted, that is, an uplink retransmission set. The UE may decide how to retransmit RLC PDUs that need to be retransmitted according to the uplink grant. The UE may retransmit all RLC PDUs requiring retransmission to the first base station, or may retransmit all RLC PDUs requiring retransmission to the second base station. Or the UE may divide the RLC PDU to be retransmitted into two parts, i.e., a first uplink retransmission subset and a second uplink retransmission subset, and retransmit the RLC PDU of the two subsets to the first base station and the second base station, respectively.

For RLC AM, the UE may update the RLC AM transmission window and the corresponding state variables to continue transmitting new RLC PDUs when the second RLC status report indicates that the first base station acknowledges receipt of a successful RLC PDU.

Alternatively, as another embodiment, the UE receives a first portion of downlink RLC PDUs from a first cell of a first base station and a second portion of downlink RLC PDUs from a second cell of a second base station, wherein the first cell and the second cell are each located on different carriers.

After the carrier of the first base station and the carrier of the second base station perform CA, the UE may perform data transmission through a first cell on the carrier of the first base station and a second cell on the carrier of the second base station.

Alternatively, as another embodiment, the UE may receive an RRC connection reconfiguration message from the first base station, where the RRC connection reconfiguration message carries the resource information of the second cell determined by the second base station.

It should be understood that the UE may also receive an RRC connection reconfiguration message from the second base station, where the RRC connection reconfiguration message carries the resource information of the second cell determined by the second base station.

Alternatively, as another embodiment, the UE may receive an RRC connection reconfiguration message from the second base station, where the RRC connection reconfiguration message carries the resource information of the first cell determined by the first base station.

It should be understood that the UE may also receive an RRC connection reconfiguration message from the first base station, where the RRC connection reconfiguration message carries the resource information of the first cell determined by the first base station.

Embodiments of the present invention will be described in detail below with reference to specific examples, and it should be noted that these examples are only for the purpose of helping those skilled in the art to better understand the embodiments of the present invention, and are not intended to limit the scope of the embodiments of the present invention.

In fig. 5, a first base station will be described as a macro base station and a second base station as a micro base station. For example, the first base station may be the macro base station 110a in fig. 1a or the macro base station 110b in fig. 1b, and the second base station may be the micro base station 120a in fig. 1a or the micro base station 120b in fig. 1 b. The UE may be UE 130a in fig. 1a or UE 130b in fig. 1 b.

In fig. 5, the macro base station serves as a user plane anchor point. The macro base station can receive downlink data issued by a packet data network (Packet Data Gateway, PGW) from the SGW through an S1-U interface, and split the downlink data, wherein one part of the downlink data is sent to the UE through a Uu interface, and the other part of the downlink data is sent to the UE by the micro base station. The macro base station can also receive uplink data from the UE through the Uu interface, receive the uplink data sent to the micro base station by the UE from the micro base station, process the two parts of uplink data, send the processed uplink data to the SGW through the S1-U interface, and send the processed uplink data to the PGW through the SGW.

The configuration process of the data splitting of fig. 5 will be described in detail below in conjunction with fig. 6.

Assuming that the UE has established an RRC connection with the macro base station, the cell of the current macro base station serves the UE. And the macro base station and the micro base station can complete the configuration process of data distribution while data transmission is carried out between the macro base station and the UE. This process will be described in detail below.

601, the ue sends a measurement report to the macro base station.

For example, the UE may generate a measurement report based on a cell reference signal (Cell Specific Reference Signal, CRS) or a channel state information reference signal (Channel State Information Reference Signal, CSI-RS). The measurement report may include RSRP measurements of cells and neighbors of the macro base station.

The macro base station determines to increase cells of the micro base station and/or establish DRB according to the measurement report 602.

Adding a second cell may be referred to as a cell of the UE aggregated micro base station. Establishing a DRB may refer to establishing a DRB for a UE by a micro base station.

In addition, the macro base station may determine the cell to which the micro base station is added according to the measurement result of the macro base station to the SRS, or may determine the cell to which the micro base station is added according to other measurement results, for example, CQI reported by the UE.

In addition, the macro base station can also determine to establish the DRB according to the QoS parameters, traffic volume, throughput, peak rate and other information of the DRB.

It should be noted that the macro base station may determine that the two processes of adding the cell of the micro base station and establishing the DRB are performed in no order, or may be performed simultaneously. For example, the macro base station may determine to add the second cell and/or to establish the DRB at the same time, or may determine to add the cell of the micro base station first, then to establish the DRB, or first to establish the DRB, then to determine to add the cell of the micro base station. The embodiment of the present invention is not limited thereto.

603, the macro base station sends a first request message to the micro base station.

The first request message may indicate that the micro base station configures a cell of the micro base station for the UE. The first request message may also instruct the micro base station to establish a DRB for the UE.

Corresponding to step 602, the macro base station may instruct the micro base station to configure the cell of the micro base station and establish the DRB at the same time in the first request message, or may send the first request message twice to the micro base station, to instruct the micro base station to configure the cell of the micro base station and establish the DRB respectively.

When the first request message indicates the micro base station to establish the DRB for the UE, the macro base station can carry configuration information of the DRB in the first request message. For example, the DRB configuration information may include at least one of: an evolved radio access bearer (Evolved Radio Access Bearer, E-RAB) identity, E-RAB QoS parameters, DRB identity, RLC configuration information, logical channel configuration information. In addition, the DRB configuration information may also include other related information. The E-RAB quality of service parameter may be a QoS parameter after the macro base station performs a offloading decision, for example, the micro base station may offload guaranteed bit rate (Guaranteed Bit Rate, GBR), the macro base station DRB offloads 60%, the micro base station offloads 40%, and the GBR parameter value sent to the micro base station is 40% multiplied by the original GBR parameter value.

The micro base station configures a cell of the micro base station according to the first request message and establishes a DRB for the UE 604.

The micro base station can conduct admission control according to the first request message, and configure the resources of the cells of the micro base station, so that the resource information of the cells of the micro base station is determined.

If the first request message indicates that DRB is established for the UE, the micro base station can establish an RLC entity and a logic channel corresponding to the DRB according to the configuration information of the DRB carried in the first request message, and set DRB parameters, RLC parameters, logic channel parameters, qoS parameters and the like. The QoS parameters may be configured according to the split ratio carried in the first request message.

Note that the micro base station may not establish the PDCP entity. Alternatively, the micro base station may establish the PDCP entity and turn the PDCP entity off.

It should also be noted that the micro base station configures the cells of the micro base station and establishes the DRBs are two processes, performed in no order. However, both processes need to be completed in order to achieve the subsequent data splitting process.

605, the micro base station sends a first response message to the macro base station.

The first response message may carry resource information of a cell of the micro base station.

606, the macro base station sends an RRC connection reconfiguration message to the UE.

The RRC connection reconfiguration message may carry resource information of the cells of the micro base station.

In general, the DRB configuration of the UE may use the previous DRB configuration. If the UE needs to reconfigure the DRB, the macro base station may carry the configuration information of the DRB in the RRC connection reconfiguration message.

607, the ue performs connection reconfiguration according to the RRC connection reconfiguration message.

The UE may configure radio resources related to the cell of the micro base station according to the resource information of the cell of the micro base station carried in the RRC connection reconfiguration message.

If the RRC connection reconfiguration message also carries the configuration information of the DRB, the UE can also perform DRB reconfiguration according to the configuration information of the DRB.

The ue sends 608 an RRC connection reconfiguration complete message to the macro base station.

And after the UE is successfully reconfigured, the UE informs the macro base station of the reconfiguration completion.

609, the macro base station sends a configuration completion message to the micro base station.

And the macro base station informs the micro base station of the completion of the connection reconfiguration of the UE through the configuration completion message.

And 610, the UE performs a random access process with the micro base station to complete uplink synchronization with the micro base station.

It should be noted that step 610 may also be performed between step 607 and step 608. If the UE completes uplink synchronization with the micro base station after step 608, the UE may also send an RRC connection reconfiguration complete message to the micro base station, which is forwarded to the macro base station by the micro base station in step 608. The UE may notify the macro base station after the random access of the micro base station is successful, so that the macro base station starts to offload data to the micro base station.

611, the macro base station transmits data with the UE, and the micro base station transmits data with the UE.

For the downlink direction, the macro base station may acquire downlink data from the SGW, and generate downlink RLC PDUs according to the downlink data.

The macro base station may send a first portion of the downlink RLC PDUs to the UE and a second portion of the downlink RLC PDUs to the micro base station. The micro base station may send a second portion of the downlink RLC PDU to the UE.

For the uplink direction, the UE may generate an uplink RLC PDU, send a first portion of the uplink RLC PDUs to the macro base station, and send a second portion of the uplink RLC PDUs to the micro base station. And the micro base station transmits the second part of uplink RLC PDU to the macro base station. And after the macro base station reorganizes and otherwise processes the two parts of uplink RLC PDUs, the two parts of uplink RLC PDUs are sent to the SGW.

It should be understood that the sequence numbers of the above processes do not mean the order of execution, and the execution order of the processes should be determined by the functions and internal logic of the processes, and should not be construed as limiting the implementation process of the embodiments of the present invention.

In the embodiment of the invention, the macro base station is used as the anchor point of the user plane, so that the macro base station and the micro base station can jointly transmit data with the UE, thereby improving the peak rate and throughput of the UE.

In addition, the UE does not need to switch between the macro base station and the micro base station, and service delay or interruption caused by switching can be avoided.

In fig. 5 and fig. 6, the macro base station may be used as the user plane anchor point, and in the embodiment of the present invention, the micro base station may also be used as the user plane anchor point. As will be described below in connection with fig. 7 and 8.

In fig. 7, a first base station is taken as a micro base station, and a second base station is taken as a macro base station as an example. For example, the first base station may be the micro base station 120a in fig. 1a or the micro base station 120b in fig. 1b, and the second base station may be the macro base station 110a in fig. 1a or the macro base station 110b in fig. 1 b. The UE may be UE 130a in fig. 1a or UE 130b in fig. 1 b.

In fig. 7, the micro base station serves as a user plane anchor point. The micro base station can receive downlink data issued by the PGW from the SGW through the S1-U interface, and split the downlink data, wherein one part of the downlink data is sent to the UE through the Uu interface, and the other part of the downlink data is sent to the UE by the macro base station. The micro base station can also receive uplink data from the UE through the Uu interface, receive the uplink data sent to the macro base station by the UE from the macro base station, process the two parts of uplink data, send the processed uplink data to the SGW through the S1-U interface, and send the processed uplink data to the PGW through the SGW.

The configuration process of the data splitting of fig. 7 will be described in detail with reference to fig. 8.

Assuming that the UE has established an RRC connection with the macro base station, the cell of the current macro base station serves the UE. And the macro base station and the micro base station can complete the configuration process of data distribution while data transmission can be performed between the macro base station and the UE. This process will be described in detail below.

Step 801 is similar to step 601 in fig. 6 and is not repeated here.

And 802, the macro base station determines to increase cells of the micro base station and/or establish DRB according to the measurement report, and determines anchor point migration.

The procedure of the macro base station determining to add the cells of the micro base station and establishing the DRB is similar to step 602 in fig. 6, and will not be repeated here.

The macro base station can determine the micro base station as an anchor point according to a shunting strategy or a shunting proportion based on relevant information such as a measurement report. For example, if the micro base station occupies a larger split ratio, for example, for GBR, the macro base station splits 30%, and the micro base station splits 70%, then the macro base station may determine to perform anchor point migration, and the micro base station is used as a user plane anchor point, that is, performs path switching, to migrate the corresponding E-RAB to the S1-U interface between the micro base station and the SGW.

In addition, in the case of splitting a plurality of DRBs, the splitting ratio of these DRBs may be kept as consistent as possible in the splitting policy, for example, in the case of splitting two DRBs, the splitting ratio of the micro base station and the splitting ratio of the macro base station may be both large in the splitting policy.

803, the macro base station sends a second request message to the micro base station.

The second request message may instruct the micro base station to configure a cell of the micro base station for the UE. The second request message may also instruct the micro base station to establish a DRB for the UE.

The second request message may also indicate the micro base station as a user plane anchor.

The procedure of step 803 is similar to step 603 in fig. 6, and in order to avoid repetition, a detailed description is omitted here.

And 804, configuring a cell of the micro base station and establishing a DRB for the UE according to the second request message by the micro base station, and preparing anchor point migration.

The process of configuring the micro base station cell for the UE is similar to step 604 in fig. 6, and is not repeated here.

If the second request message indicates that the DRB is established for the UE, the micro base station can establish a PDCP entity, an RLC entity and a logic channel corresponding to the DRB according to the configuration information of the DRB carried in the second request message, and set DRB parameters, PDCP parameters, RLC parameters, logic channel parameters, qoS parameters and the like. The QoS parameters may be configured according to the split ratio carried in the second request message.

Unlike step 604, in step 804, the micro base station needs to prepare for anchor point migration.

805, the micro base station sends a second response message to the macro base station.

The second response message may carry resource information of the cell of the micro base station. The second response message may also indicate that the micro base station is ready for anchor migration.

806, the macro base station sends an RRC connection reconfiguration message to the UE.

807, the ue performs RRC connection reconfiguration according to the RRC connection reconfiguration message.

808, the ue sends an RRC connection reconfiguration complete message to the macro base station.

809, the macro base station sends a configuration completion message to the micro base station.

810, the micro base station sends a path switching request message to the MME.

The path switch request message may indicate switching of the data transmission path to the micro base station.

811, the mme sends a bearer change request message to the SGW.

The bearer change request message may request switching of the data transmission path from the SGW.

812, the sgw switches paths according to the bearer change request message.

813, the sgw sends a bearer change response message to the MME.

814, the mme sends a path switch response message to the micro base station.

And 815, the UE performs a random access process with the micro base station to complete uplink synchronization with the micro base station.

It should be noted that step 815 may be performed in parallel with the path switching process of steps 810 through 814.

Prior to step 815, the macro base station may proceed with the data transmission procedure of the UE to complete transmission of data already buffered in Radio Bearers (RBs) (including SRBs and DRBs).

816, data is transmitted between the micro base station and the UE, and data is transmitted between the macro base station and the UE. And transmitting data between the micro base station and the SGW.

For the downlink direction, the micro base station may acquire downlink data from the SGW, and generate downlink RLC PDU according to the downlink data.

The micro base station may send a first portion of the downlink RLC PDUs to the UE and a second portion of the downlink RLC PDUs to the macro base station. The macro base station may send a second portion of downlink RLC PDUs to the UE.

For the uplink direction, the UE may generate an uplink RLC PDU, send a first portion of the uplink RLC PDUs to the micro base station, and send a second portion of the uplink RLC PDUs to the macro base station. And the macro base station transmits the second part of uplink RLC PDU to the micro base station. And the micro base station reorganizes the two parts of RLC PDUs and sends the two parts of RLC PDUs to the SGW after subsequent processing.

The example of the control plane protocol stack of fig. 9 may be applied to the examples of fig. 5 to 8 described above. Assuming initially that the UE and the macro base station have established an RRC connection, the control plane functions are provided by the macro base station, the control plane message transmissions are all between the macro base station and the UE, and no offloading is performed for the data of the signaling radio bearers (Signaling Radio Bearer, SRBs). The signaling related to the control plane between the macro base station and the micro base station can be performed through an X2 interface or a direct connection between the macro base station and the micro base station. It should be understood that, although fig. 9 illustrates an example in which SRB is not split, in an embodiment of the present invention, data of SRB may be split.

As shown in fig. 9, the connection between the macro base station and the RRC, PDCP, RLC, MAC, PHY layer of the UE represents the logical connection of the peer protocol layer on the radio interface between the macro base station and the UE, which means that the data sent by the sender at each protocol layer is processed by the peer protocol layer of the receiver to form the data with the same format and content as the sender.

For communication between the macro base station and the UE, the control plane data transmission procedure may be as follows: at the transmitting end side, after being processed by each protocol layer of PDCP, RLC, MAC, PHY, the RRC message is sent to the receiving end through the wireless interface, and control plane data received by the receiving end through the wireless interface is processed by the PHY layer first and then sequentially submitted to MAC, RLC, PDCP and the RRC layer for processing. It should be understood that, here, the transmitting end is a macro base station, and the receiving end is a UE. The transmitting end is UE, and the receiving end is macro base station.

There may be no transmission of control plane data between the micro base station and the UE.

It should be noted that although the example of fig. 9 is described by taking the macro base station as an example to provide the control plane function. However, in the embodiment of the present invention, the macro base station and the micro base station may jointly provide the control plane function, for example, when the UE in the common coverage area of the macro base station and the micro base station has RRC connection with both the macro base station and the micro base station at the beginning, the macro base station and the micro base station may jointly provide the control plane function.

In fig. 10, assuming that the macro base station is a user plane anchor point, the macro base station needs to split by 2 DRBs.

1) The user plane protocol stack of the macro base station is described as follows:

on the macro base station side, DRB to be shunted is DRB1 and DRB2, and PDCP entity PDCP1, RLC entity RLC1 and logical channel LCH1 corresponding to the DRB1 are established; establishing PDCP2, RLC2 and LCH2 corresponding to the DRB 2; logical channels are located between the RLC layer and the MAC layer, LCH1 and LCH2 are not shown in fig. 10. Assuming that carriers participating in aggregation in the macro base station are CC1, corresponding cells are Primary cells (PCell), the PCell sets a MAC layer MAC1 and a PHY layer PHY1, and sets an HARQ entity HARQ1 in the MAC layer. LCH1 corresponding to DRB1 and LCH2 corresponding to DRB2 are mapped to a downlink shared transport channel (Downlink Share Channel, DL-SCH) DL-SCH1 or an uplink shared transport channel (Uplink Shared Channel, UL-SCH) UL-SCH1 through the MAC layer, the transport channels being located between the MAC layer and the PHY layer, the DL-SCH1 and the UL-SCH1 not being shown in FIG. 10.

The connection between the macro base station and the PDCP, RLC, MAC, PHY of the UE represents the logical connection of the peer protocol layers on the wireless interface between the macro base station and the UE, and represents that the data sent by the sender at each protocol layer is processed at the peer protocol layer of the receiver to form the data with the same format and content as the sender. Wherein the DRB1 of the macro base station corresponds to the DRB1 of the UE, and correspondingly, the PDCP1 and the RLC1 in the macro base station correspond to the PDCP1 and the RLC1 of the UE; PDCP2 and RLC2 in the macro base station correspond to PDCP2 and RLC2 of the UE.

The connection between the macro base station and the micro base station at the RLC layer means that data distribution is performed at the RLC layer, and RLC1 and RLC2 of the macro base station correspond to RLC1 and RLC2 of the micro base station, respectively.

For communication between the macro base station and the UE, the user plane data transmission procedure may be as follows:

for downlink data, a network protocol (Internet Protocol, IP) data packet from the SGW is processed by each protocol layer of PDCP, RLC, MAC, PHY at the macro base station and then sent to the UE through the radio interface. The UE may first process data received over the radio interface through the PHY layer and then sequentially submit the data to the MAC, RLC and PDCP layers for processing.

For uplink data, the UE processes the IP data packet from the application layer through each protocol layer of PDCP, RLC, MAC, PHY and sends the IP data packet to the macro base station through the radio interface. The macro base station processes the data received through the wireless interface through the PHY layer first and then sequentially delivers the data to the MAC, RLC and PDCP layers for processing.

2) The user plane protocol stack of the micro base station is described as follows:

on the micro base station side, corresponding DRB to be shunted is DRB1 and DRB2, which are respectively used for shunting the data of DRB1 and DRB2 of the macro base station, and shunting is carried out in the RLC layer. The RLC layer of the micro base station provides a transmission buffer and a retransmission buffer and can support an RLC PDU re-segmentation function. DRB1 sets a corresponding RLC entity RLC1 and a logical channel LCH1; setting corresponding RLC2 and LCH2 by the DRB 2; logical channels are located between the RLC layer and the MAC layer, LCH1 and LCH2 are not shown in fig. 10. The carrier wave participating in aggregation in the micro base station is CC2, the corresponding Cell is a Secondary Cell (SCell), the SCell is provided with a MAC layer MAC2 and a PHY layer PHY2, and the MAC layer is provided with an HARQ entity HARQ2. Both the logical channel of DRB1 and the logical channel of DRB2 are mapped to a transport channel DL-SCH2 or UL-SCH2 through the MAC layer, the transport channel being located between the MAC layer and the PHY layer, the DL-SCH2 and the UL-SCH2 not being shown in FIG. 10.

The connection between the RLC, MAC and PHY of the micro base station and the UE represents the logical connection of the peer protocol layers on the radio interface between the micro base station and the UE, which means that the data sent by the sender at each protocol layer is processed at the peer protocol layer of the receiver to form the data with the same format and content as the sender. Wherein the DRB1 of the micro base station corresponds to the DRB1 of the UE, and correspondingly, the RLC1 of the micro base station corresponds to the RLC1 of the UE; RLC2 of the micro base station corresponds to RLC2 of the UE.

For communication between the micro base station and the UE, the user plane data transmission procedure may be as follows:

for downlink data, the micro base station can store the RLC PDU from the macro base station in a transmission buffer of a corresponding RLC entity to wait for scheduling, process the RLC PDU through each protocol layer of RLC, MAC and PHY, and transmit the RLC PDU to the UE through a wireless interface. If the complete RLC PDU cannot be transmitted due to the limitation of radio resources when the RLC PDU is transmitted for the first time, the segmentation processing can be carried out on the RLC PDU; it should be noted that segmentation in this case is handled as a re-segmentation of RLC PDUs according to the existing protocol, rather than as segmentation of RLC SDUs according to the existing protocol. The UE may first process data received over the radio interface through the PHY layer and then forward the processed data to the MAC, RLC and PDCP layers.

For uplink data, the UE may process the IP data packet from the application layer through the protocol layers PDCP, RLC, MAC and PHY and then send the IP data packet to the micro base station through the radio interface. The data received by the micro base station through the wireless interface is processed by the PHY layer and then sequentially submitted to the MAC and the RLC, and the RLC PDU formed by the RLC layer is sent to the RLC entity corresponding to the macro base station through the X2 interface.

3) The user plane protocol stack of the UE is described as follows:

on the UE side, DRB is DRB1 and DRB2, and PDCP entity PDCP1, RLC entity RLC1 and logical channel LCH1 corresponding to DRB1 are established; establishing PDCP2, RLC2 and LCH2 corresponding to the DRB 2; logical channels are located between the RLC layer and the MAC layer, LCH1 and LCH2 are not shown in fig. 10. The UE may configure a MAC layer containing a multiplexing/de-multiplexing entity (multiplexing/de-multiplexing), which is not shown in fig. 10. After multiplexing/demultiplexing the entities, two HARQ entities HARQ1 and HARQ2 are configured, corresponding to the PCell of the macro base station and the SCell of the micro base station, respectively, aggregated by the UE. The PCell configures one PHY layer PHY1, and the SCell configures one PHY layer PHY2 corresponding to HARQ1 and HARQ2 of the MAC layer, respectively.

Both the logical channels of DRB1 and the logical channels of DRB2 are mapped to transport channels DL-SCH1 or UL-SCH1, or DL-SCH2 or UL-SCH2 through the MAC layer, the transport channels being located between the MAC layer and the PHY layer, and DL-SCH1, UL-SCH1, DL-SCH2, and UL-SCH2 being not shown in FIG. 10.

The communication methods of the UE and the macro base station, and the micro base station are similar to those described in the macro base station and the micro base station, and in order to avoid repetition, the description is omitted here.

In the control plane protocol stack of fig. 9 and the user plane protocol stack of fig. 10 described above, layer2 (Layer 2) may include a PDCP Layer, an RLC Layer, and a MAC Layer.

As shown in fig. 11, PDCP layer main functions may include header compression (Robust Header Compression, ROHC), security (security), and the like, and security functions may include integrity protection (integrity protection) and ciphering (encryption).

RLC layer primary functions may include segmentation, re-segmentation, and automatic repeat request (Automatic Retransmission Request, ARQ), etc.

The MAC layer main functions may include scheduling/priority handling, multiplexing/demultiplexing, HARQ, etc.

A service access point (Service Access Point, SAP) between the PDCP layer and the upper application layer, the SAP between the PDCP layer and the RLC layer providing RBs. The SAP between the RLC layer and the MAC layer provides LCH. The SAP between the MAC layer and the physical layer provides transport channels (Transport Channel), which may include DL-SCH and UL-SCH.

The macro base station may provide the UE with PCell, and its MAC layer may set 1 HARQ entity.

In fig. 12, the DRB split from the RLC layer is exemplified. The PDCP entity and corresponding functions are not set at the micro base station. The RLC layer of the micro base station may correspond to an extension of the RLC layer of the macro base station, providing RLC layer part functions, not all RLC functions.

The micro base station receives RLC PDUs transmitted by the RLC layer of the macro base station through the X2 interface or direct connection, and stores the RLC PDUs in a transmission buffer of the RLC layer of the micro base station. The micro base station can also receive an RLC status report sent by the RLC layer of the macro base station through the X2 interface or direct connection, and retransmit RLC PDUs to be retransmitted to the UE according to the RLC status report. The micro base station can receive the RLC PDU sent by the UE, store in the receiving buffer of the RLC layer of the micro base station, and forward to the macro base station.

The function of the MAC layer is similar to that of the macro base station MAC layer in fig. 11, and in order to avoid repetition, a description thereof will be omitted.

The micro base station may provide SCell for the UE with 1 HARQ entity set by its MAC layer.

In fig. 13, the PDCP, RLC and MAC layers of the UE function similarly to the corresponding protocol layer functions of the macro base station in fig. 11, and in order to avoid repetition, a detailed description is omitted here.

The MAC layer of the UE may configure 2 HARQ entities corresponding to CC1 provided by the macro base station and CC2 provided by the micro base station, respectively. Accordingly, the HARQ entity on CC1 may be mapped to the DL-SCH and the UL-SCH on CC1, and the HARQ entity on CC2 may be mapped to the DL-SCH and the UL-SCH on CC2. Logical channels LCH1 and LCH2 of the UE may be mapped to DL-SCH and UL-SCH on CC1 or DL-SCH and UL-SCH on CC 1.

It should be noted that if the macro base station and/or the micro base station provide more CCs, respectively, for example, the macro base station and the micro base station provide two CCs, respectively, two HARQ entities may be provided at the MAC layer in the layer 2 structure of the macro base station, respectively corresponding to the two CCs provided by the macro base station, and the PDCP and RLC layers have the same structure as the PDCP and RLC layers in fig. 11. The MAC layer in the layer 2 structure of the micro base station may be provided with two HARQ entities corresponding to the two CCs provided by the micro base station, respectively, and the RLC layer has the same structure as that of the RLC layer in fig. 12.

And four HARQ entities may be set in the MAC layer in the layer 2 structure of the UE, corresponding to two CCs provided by the macro base station and two CCs provided by the micro base station, respectively.

The downlink data transmission process according to the embodiment of the present invention will be described in detail below with reference to the above-mentioned user plane protocol stack of fig. 10. Fig. 14 is a schematic flow chart of a process of a method of transmitting data according to an embodiment of the present invention. In fig. 14, the data transmission process in the downstream direction in step 611 of fig. 6 will be described in detail.

1401, the macro base station generates a downlink PDCP PDU and delivers it to the RLC layer.

The macro base station takes the downlink IP data packet from the SGW as PDCP SDU, generates PDCP PDU after the treatments of PDCP layer header compression, encryption, PDCP Sequence Number (SN) increase and the like, and submits the PDCP PDU to the RLC layer as the RLC SDU. The macro base station submits the PDCP PDU in PDCP1 to RLC1 and the PDCP PDU in PDCP2 to RLC2.

1402, the macro base station determines a first portion of downlink RLC PDUs under the responsibility of the macro base station and a second portion of downlink RLC PDUs under the responsibility of the micro base station.

The macro base station may determine the amount of data to be shunted, i.e. which downlink RLC SDUs are shunted to the macro base station and which downlink RLC SDUs are shunted to the micro base station, according to a DRB shunting strategy and QoS parameter configuration that are determined or negotiated in advance.

For downlink RLC SDUs (radio link control) which are responsible for a macro base station, the MAC layer of the macro base station can determine the data quantity which can be scheduled in a certain transmission time interval (Transmission Time Interval, TTI) according to QoS requirements and the radio resource condition of the macro base station, and indicates the size of downlink RLC PDU to be generated by the RLC layer; the MAC layer may indicate the total size of one or more downlink RLC PDUs to be generated by the RLC layer; the RLC layer may perform segmentation, concatenation, and header information processing such as adding RLC SN to the downlink RLC SDU according to the downlink RLC PDU size indicated by the MAC layer, to generate a first part of downlink RLC PDU. RLC1 and RLC2 in the macro base station may each generate different downlink RLC PDUs. In a certain TTI, one or more different downlink RLC PDUs may be generated in RLC1 and RLC2, respectively, or one or more different downlink RLC PDUs may be generated only by RLC1 or RLC 2.

For the downlink RLC SDU to be distributed to the micro base station, the MAC layer of the macro base station can determine the data quantity of a certain TTI which can be distributed to the micro base station according to the distribution decision and QoS requirement, thereby indicating the size of the downlink RLC PDU to be generated by the RLC layer; the MAC layer may indicate the total size of one or more downlink RLC PDUs to be generated by the RLC layer; the RLC layer may perform segmentation, concatenation, and header information processing such as adding RLC SN to the downlink RLC SDU according to the downlink RLC PDU size indicated by the MAC layer, to generate a second part of downlink RLC PDU. In a certain TTI, RLC1 and RLC2 may each generate one or more different RLC PDUs to be shunted to the micro base station, or may generate one or more different downlink RLC PDUs to be shunted to the micro base station by RLC1 or RLC2 alone.

The macro base station sends 1403 a first part of downlink RLC PDU to the UE.

The RLC layer of the macro base station may submit the generated first part of downlink RLC PDU to the MAC layer of the macro base station as a MAC SDU, and after multiplexing (multiplexing) with the MAC SDU of the present logical channel and/or other logical channels, generate a MAC PDU or a Transport Block (TB), and the first part of downlink RLC PDU in RLC1 and RLC2 may be multiplexed in the same TB. After the TB is submitted to the PHY layer of the macro base station, it is transmitted by the PHY layer to the UE on a physical downlink shared channel (Physical downlink shared channel, PDSCH) on the PCell.

1404, the macro base station sends a second portion of downlink RLC PDU to the micro base station.

The macro base station may send a second portion of downlink RLC PDUs to the micro base station via an X2 interface or direct connection between the macro base station and the micro base station.

1405, the micro base station prepares to issue a second part of downlink RLC PDU.

After receiving the second part of downlink RLC PDU of RLC1 of the macro base station, the micro base station may store it in the transmission buffer of micro base station RLC 1. After receiving the second part of downlink RLC PDU of RLC2 of the macro base station, the micro base station may store it in the transmission buffer of the micro base station RLC 2.

And the MAC layer of the micro base station determines the data quantity which can be scheduled by a certain TTI according to the split decision and QoS requirement, and indicates the size of the downlink RLC PDU to be generated by the RLC layer.

The MAC layer may indicate to the RLC layer the total size of one or more downlink RLC PDUs. The MAC layer may indicate to the RLC layer the original downlink RLC PDU size, meaning that one or more original downlink RLC PDUs stored in the RLC transmission buffer are directly handed over to the MAC layer as MAC SDUs without any processing. Or the MAC layer may indicate to the RLC layer a total downlink RLC PDU size smaller than the original downlink RLC PDU size, meaning that after re-segmentation of the original downlink RLC PDU, a downlink RLC PDU Segment (Segment) is generated and submitted to the MAC layer without adding an additional RLC SN at the RLC layer.

The RLC layer of the micro base station does not need to support RLC PDU concatenation functions. It should be noted that in a certain TTI, one or more different original downlink RLC PDUs or downlink RLC PDU segments may be delivered to the MAC layer at RLC1 and RLC2, respectively, and only the last downlink RLC PDU may be a downlink RLC PDU segment, or only the downlink RLC PDU may be delivered to the MAC layer by RLC1 or RLC 2.

The micro base station can improve the priority of the UE in the CA scene between the base stations to ensure the wireless resources required by the data distribution, so that enough downlink resources can be distributed to send the original second part of downlink RLC PDU distributed to the micro base station. Or if the radio resource allocated to the UE cannot accommodate the original second partial downlink RLC PDU due to radio interface resource limitation, re-segmentation processing of the original second partial downlink RLC PDU is required at the RLC layer of the micro base station.

1406, the micro base station sends a second part of downlink RLC PDU to the UE.

The RLC layer of the micro base station may forward the original second part of downlink RLC PDU or the downlink RLC PDU segment after re-segmentation of the second part of downlink RLC PDU to the MAC layer of the micro base station as a MAC SDU, and after multiplexing with the MAC SDU of the present logical channel and/or other logical channels, generate a MAC PDU or a TB, where the downlink RLC PDU in RLC1 and RLC2 may be multiplexed in the same TB. After the TB is submitted to the PHY layer of the micro base station, it is transmitted to the UE by the PHY layer on the PDSCH on the SCell.

The micro base station may send downlink RLC PDUs in ascending order of RLC SN. For RLC AM, the micro base station does not need to maintain RLC AM transmission windows.

1407, the ue receives the first portion downlink RLC PDU and the second portion downlink RLC PDU, and reassembles the first portion downlink RLC PDU and the second portion downlink RLC PDU to form a downlink RLC SDU.

After receiving physical layer data on the PDSCH of the PCell and the PDSCH of the SCell, the UE submits corresponding TBs to HARQ1 and HARQ2 corresponding to the MAC layer after processing the physical layer data successfully by PHY1 and PHY2, respectively, and the MAC layer demultiplexes the TBs and submits MAC SDUs, namely RLC PDUs, to corresponding RLC entities RLC1 and RLC2. The RLC layer of the UE may be divided into RLC1 and RLC2 according to the DRB instead of PCell and SCell, and the HARQ entity and PHY layer of the MAC layer may be divided according to different serving cells, which is transparent to the RLC layer of the UE.

After receiving the RLC PDU submitted by the MAC layer, the RLC layer of the UE may perform a corresponding RLC PDU receiving process according to whether the RLC mode is RLC UM or RLC AM (each RLC entity is one of two RLC modes), and the RLC PDU successfully received is sequenced according to RLC SN, and constitutes an RLC SDU, and submitted to the PDCP layer.

It should be understood that the sequence numbers of the above processes do not mean the order of execution, and the execution order of the processes should be determined by the functions and internal logic of the processes, and should not be construed as limiting the implementation process of the embodiments of the present invention. For example, step 1403 may be performed in parallel with steps 1404 to 1406, or step 1404 may be performed first, followed by step 1403.

In the transmission of the first and second partial downlink RLC PDUs, a case where retransmission is required may occur due to a communication condition, and a data retransmission process will be described in detail with reference to fig. 15 and 16.

In fig. 15, a retransmission procedure of the downlink RLC PDU for the RLC AM in fig. 14 will be described in detail.

1501, the ue receives the first portion downlink RLC PDU and the second portion downlink RLC PDU, and generates a first RLC status report according to the reception conditions of the first portion downlink RLC PDU and the second portion downlink RLC PDU.

It should be noted that the UE may generate the first RLC status report corresponding to RLC1 according to the reception conditions of the first and second partial downlink RLC PDUs of RLC1, and may generate the first RLC status report corresponding to RLC2 according to the reception conditions of the first and second partial downlink RLC PDUs of RLC 2.

1502, the ue sends a first RLC status report to a macro base station.

The UE may send a first RLC status report corresponding to RLC1 and a first RLC status report corresponding to RLC2, respectively, to the macro base station.

1503, when the first RLC status report indicates that the RLC PDU of the first portion of downlink RLC PDUs needs to be retransmitted, the macro base station retransmits the RLC PDU of the first portion of downlink RLC PDUs, which needs to be retransmitted, to the UE. And when the UE is indicated to confirm that the receiving of the successful RLC PDU in the first RLC status report, the macro base station updates an RLC AM sending window and a corresponding state variable so as to continue to send a new RLC PDU.

In conjunction with fig. 10 and fig. 14, RLC1 and RLC2 of the macro base station may determine, according to the corresponding first RLC status report, which RLC PDUs in the first part of downlink RLC PDUs need to be retransmitted (retransmission), and which RLC PDUs in the second part of downlink RLC PDUs need to be retransmitted by the micro base station, respectively.

RLC1 and RLC2 of the macro base station may retransmit RLC PDUs required to be retransmitted in the first part of downlink RLC PDUs corresponding to each of the RLC PDUs to the UE, respectively.

1504, when the first RLC status report indicates an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs, the macro base station sends the first RLC status report or a retransmission message to the micro base station.

The macro base station may send a first RLC status report to the micro base station over the X2 interface or a direct connection.

The macro base station may also generate a retransmission message according to the first RLC status report, where the retransmission message may indicate an RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs.

1505, the micro base station retransmits the RLC PDU needing to be retransmitted in the second part of downlink RLC PDU to the UE according to the first RLC status report or retransmission message.

In conjunction with fig. 10 and fig. 14, RLC1 and RLC2 of the micro base station may determine, according to the corresponding first RLC status report, which RLC PDUs in the second portion of downlink RLC PDUs corresponding to each other need to be retransmitted. RLC1 and RLC2 of the micro base station may retransmit RLC PDUs to be retransmitted in the second part of downlink RLC PDUs corresponding to each other to the UE, respectively.

For RLC PDU requiring retransmission in the second part of downlink RLC PDU, if the number of times of retransmission of the micro base station reaches a predetermined number of times but has not reached the maximum number of times of retransmission, the micro base station may notify the macro base station of retransmission. The micro base station can send the second part of downlink RLC PDU to be retransmitted to the macro base station, or the macro base station keeps a backup in a retransmission buffer for each RLC PDU in the second part of downlink RLC PDU shunted to the micro base station, and the micro base station directly informs the macro base station of RLC PDU SN needing retransmission in the second part of downlink RLC PDU.

Or the macro base station receives the first RLC state report of the UE, and the macro base station can retransmit under the condition that the macro base station judges that the retransmission of the micro base station is needed and the retransmission times of the macro base station reach the preset times but the maximum retransmission times are not reached. In this case, the macro base station may notify the micro base station to transmit the related RLC PDU to be retransmitted back to the macro base station, or the macro base station may keep a backup in the retransmission buffer for each RLC PDU in the second portion of the downlink RLC PDUs shunted to the micro base station; when the macro base station decides to retransmit itself, the macro base station modifies the state of the corresponding RLC PDU to be retransmitted to an Acknowledgement (ACK) state in the first RLC status report sent to the micro base station.

It should be understood that the sequence numbers of the above processes do not mean the order of execution, and the execution order of the processes should be determined by the functions and internal logic of the processes, and should not be construed as limiting the implementation process of the embodiments of the present invention. For example, step 1503 may be performed in parallel with steps 1504 to 1505, or steps 1504 and 1505 may be performed first, followed by step 1503.

In fig. 15, the UE may send a first RLC status report to the macro base station. In addition, the UE may also send a first RLC status report to the micro base station. As will be described below in connection with fig. 16.

In fig. 16, a retransmission procedure of the downlink RLC PDU for the RLC AM in fig. 14 will be described in detail.

1601, the ue generates a first RLC status report according to the reception status of the first portion of downlink RLC PDU and the second portion of downlink RLC PDU.

1602, the ue sends a first RLC status report to a micro base station.

If the SCell has uplink resources, the UE may send a first RLC status report to the micro base station.

1603, when the first RLC status report indicates that the RLC PDU of the second portion of downlink RLC PDUs needs to be retransmitted, the micro base station retransmits the RLC PDU of the second portion of downlink RLC PDUs needs to be retransmitted to the UE.

1604, the micro base station sends a first RLC status report to the macro base station.

1605, the macro base station retransmits the RLC PDU which needs to be retransmitted in the first part of downlink RLC PDUs to the UE according to the first RLC status report.

And when the first RLC status report indicates the RLC PDU which needs to be retransmitted in the first part of downlink RLC PDUs, the macro base station retransmits the RLC PDU which needs to be retransmitted in the first part of downlink RLC PDUs to the UE.

When the UE is instructed to confirm that the RLC PDU is received successfully in the first RLC status report, the first base station may be caused to update the RLC AM transmission window and the corresponding state variables to continue transmitting new RLC PDUs.

Referring to fig. 10 and 14, RLC1 and RLC2 of the macro base station may determine, according to the corresponding first RLC status report, which RLC PDUs in the corresponding first partial downlink RLC PDUs need to be retransmitted. RLC1 and RLC2 of the macro base station may retransmit RLC PDUs required to be retransmitted in the first part of downlink RLC PDUs corresponding to each of the RLC PDUs to the UE, respectively. For RLC PDUs requiring retransmission in the second part of downlink RLC PDUs, if the number of times of retransmission of the micro base station reaches a predetermined number of times but has not reached the maximum number of times of retransmission, processing may be performed according to the method described in fig. 15. In order to avoid repetition, a description thereof is omitted.

With reference to fig. 15 and fig. 16, it should be understood that the UE may send a first RLC status report corresponding to RLC1 to the macro base station and a first RLC status report corresponding to RLC2 to the micro base station, respectively; or the UE may send the first RLC status report corresponding to RLC1 to the micro base station and send the first RLC status report corresponding to RLC2 to the macro base station, respectively.

It should be understood that the sequence numbers of the above processes do not mean the order of execution, and the execution order of the processes should be determined by the functions and internal logic of the processes, and should not be construed as limiting the implementation process of the embodiments of the present invention. For example, step 1603 may be performed in parallel with steps 1604 to 1605, or steps 1604 and 1605 may be performed first, followed by step 1603.

The uplink data transmission process according to the embodiment of the present invention will be described in detail below with reference to the above-mentioned user plane protocol stack of fig. 10. Fig. 17 is a schematic flow chart of a procedure of a method of transmitting data according to an embodiment of the present invention. In fig. 17, the data transmission process in the uplink direction in step 611 of fig. 6 will be described in detail.

1701, the ue sends a buffer status report (Buffer Status Report, BSR) to the macro base station.

When the macro base station has available uplink resources, the UE may send a BSR to the macro base station.

Note that in step 1701, the UE may also send a BSR to the micro base station when the micro base station has available uplink resources.

At most, the UE may transmit one regular BSR (regular BSR) or periodic BSR (periodic BSR) type BSR in a certain TTI. If the macro base station and the micro base station allocate uplink grants to the UE in a certain TTI, the UE can only send one regular BSR or periodic BSR to the macro base station or the micro base station, but cannot send the regular BSR or periodic BSR to the macro base station and the micro base station at the same time.

The BSR reflects the amount of data available for all logical channels in each logical channel group (Logical Channel Group, LCG) of the UE after a certain TTI generates a MAC PDU, typically a maximum of 4 logical channel groups. There are two ways to determine the buffer size level (buffer size level) in each LCG in the BSR, including a BSR and an extended BSR, where either the BSR or the extended BSR may be configured by RRC.

BSR formats may be classified as long BSR (long BSR), short BSR (short BSR), or truncated BSR (truncated BSR). The long BSR may include buffer data amounts of 4 LCGs, and each logical channel group may include a buffer size (buffer size) including a total amount of available data in all logical channels in the logical channel group, including data amounts to be transmitted by the RLC layer and the PDCP layer.

The types of BSR or extended BSR can be classified into regular BSR, periodic BSR, and padding BSR (padding BSR). For example, when uplink data arrives for a high priority logical channel, a regular BSR is triggered. When the periodic BSR timer expires, the periodic BSR is triggered. When the uplink resource allocated by the UE has a padding bit (padding bit) after accommodating the MAC SDU, the padding BSR may be carried in the padding bit. The regular BSR and the periodic BSR have a higher priority than the padding BSR.

1702, the macro base station allocates uplink resources for the UE according to the BSR.

The macro base station may determine the amount of data to be shunted according to a DRB shunt policy and QoS parameter configuration that are determined or negotiated in advance. And allocating uplink resources for the UE according to the data quantity, the wireless condition or the QoS parameters and the like which are distributed to the base station.

1703, the macro base station sends first uplink grant (UL grant) information to the UE, where the first uplink grant information indicates uplink resources allocated by the macro base station for the UE.

After allocating uplink resources for the UE, the macro base station transmits first uplink grant information to the UE through a physical downlink control channel (Physical downlink control channel, PDCCH).

1704, the macro base station transmits a BSR to the micro base station.

The macro base station may forward the BSR to the micro base station over an X2 interface or a direct connection.

In addition, the macro base station may modify the buffer data amount of the corresponding logical channel group in the BSR according to the data amount to be shunted to the micro base station, and send the modified BSR to the micro base station. The macro base station may indicate whether the transmitted BSR is the original BSR or the modified BSR in the above-mentioned X2 interface message, or negotiate whether the original BSR or the modified BSR is transmitted in advance.

1705, the micro base station allocates uplink resources for the UE according to the BSR.

If the BSR received by the micro base station is the original BSR, determining the data quantity of the micro base station to be shunted according to a predetermined or negotiated DRB shunt strategy and QoS parameter configuration, and modifying the buffer data quantity of the corresponding logical channel group in the original BSR.

If the BSR received by the micro base station is the modified BSR, the buffer data volume of the corresponding logical channel group can be directly used, and uplink resources can be allocated to the UE according to the buffer data volume, radio conditions, qoS parameters and the like.

1706, the micro base station sends second uplink authorization information to the UE, where the second uplink authorization information indicates uplink resources allocated by the micro base station to the UE.

The micro base station can send the second uplink authorization information to the UE through the PDCCH.

1707, the ue determines the data amount to be sent for each logical channel according to the first uplink grant information and the second uplink grant information.

The UE may determine, according to the logical channel priority processing procedure, an amount of data to be transmitted on the uplink grant of the PCell and/or the SCell for each logical channel according to the first uplink grant information and the second uplink grant information. The uplink RLC PDU size is indicated by MAC to RLC1 and/or RLC 2. The MAC layer may indicate the total size of one or more uplink RLC PDUs to be generated by the RLC layer.

1708, the ue generates an uplink RLC PDU.

The RLC layer of the UE may perform segmentation, concatenation, and header information processing such as adding RLC SN to the uplink RLC SDU according to the uplink RLC PDU size indicated by the MAC layer, and generate the uplink RLC PDU. RLC1 and RLC2 each generate a different uplink RLC PDU. In a certain TTI, one or more different uplink RLC PDUs may be generated in RLC1 and RLC2, respectively, or only RLC1 or RLC2 may generate uplink RLC PDUs.

1709, the ue transmits a first part of uplink RLC PDUs to the macro base station on the PCell.

RLC1 and RLC2 of the UE may submit uplink RLC PDUs generated according to the MAC indication to the MAC as uplink MAC SDUs.

And after the MAC multiplexes the uplink MAC SDU and the uplink MAC SDU of the logic channel and/or other logic channels, generating an uplink MAC PDU or called a TB. RLC PDUs in RLC1 and RLC2 may be multiplexed in the same TB. The MAC submits the TBs generated for HARQ1 to PHY1, which sends them to the macro base station on the physical uplink shared channel (Physical uplink shared channel, PUSCH) of the PCell.

1710, the ue sends a second part of the uplink RLC PDUs to the micro base station on the Scell.

The MAC of the UE submits the TB generated for HARQ2 to PHY2, which sends it to the micro base station on PUSCH of SCell.

1711, the micro base station sends the second part of uplink RLC PDU to the macro base station.

The micro base station submits the data received on the PUSCH of the SCell to the RLC1 and the RLC2 after being processed by the PHY2 and the MAC2, and stores the received buffer areas corresponding to the RLC1 and the RLC 2. For RLC AM, the micro base station need not maintain RLC AM receive windows and perform a re-ordering (re-ordering) function.

The micro base station may send a second part of the uplink RLC PDU to the macro base station via X2 or a direct connection.

The macro base station receives RLC PDUs from the micro base station and stores in the reception buffers corresponding to RLC1, RLC 2.

1712, the macro base station receives the first part of uplink RLC PDU and the second part of uplink RLC PDU, and reassembles the first part of uplink RLC PDU and the second part of uplink RLC PDU.

The macro base station may submit the data received from the UE on the PUSCH of the PCell to RLC1 and RLC2 after PHY1 and MAC1 processing, and store the reception buffers corresponding to RLC1 and RLC 2.

The macro base station may also store the second portion of uplink RLC PDUs received from the micro base station in the reception buffers corresponding to RLC1 and RLC 2.

The macro base station can reorganize the first part of uplink RLC PDU and the second part of uplink RLC PDU according to the comprehensive receiving conditions in the RLC1 and RLC2 receiving buffer areas, and submit the first part of uplink RLC PDU and the second part of uplink RLC PDU to the PDCP layer according to the ascending order of RLC SN. RLC1 and RLC2 may perform a corresponding RLC PDU receiving process according to whether the RLC mode is RLC UM or RLC AM (each RLC entity is one of two RLC modes), and deliver successfully received uplink RLC PDUs to the PDCP layer in RLC SN ascending order.

It should be noted that in the above procedure, if the UE transmits a BSR to the micro base station, the micro base station may forward the received BSR to the macro base station.

Further, since both the macro base station or the micro base station may receive the BSR transmitted by the UE and the BSR transmitted by the other base station, considering the delay of the X2 interface, if the macro base station or the micro base station continuously or simultaneously receives the BSRs transmitted in a plurality of different directions in a short time, it may be difficult for the macro base station and the micro base station to determine which BSR is the latest. To solve this problem, time information, such as time stamp (time stamp) information or system frame number (System Frame Number, SFN) and subframe number (subframe) information of the PCell or SCell, may be added to the BSR transmitted by the UE.

In addition, the method for the UE to send BSR may also be: when the PCell provided by the macro base station and the SCell provided by the micro base station are respectively provided with uplink resources in a certain TTI, the UE simultaneously transmits a regular BSR or a periodic BSR on the PCell and the SCell, and indicates whether a flag of forwarding is needed or not in the BSR, and the flag is set as not needing forwarding. The BSR transmitted simultaneously on the PCell and SCell is required to be the same buffer size level value for the same LCG. When the macro base station and the micro base station respectively provide a plurality of CCs and uplink resources are allocated to the plurality of CCs of the macro base station and the micro base station in a certain TTI, the UE can only send one regular BSR or periodic BSR in the uplink resources of all the CCs of the macro base station and can only send one regular BSR or periodic BSR in the uplink resources of all the CCs of the micro base station.

In the transmission of the first part of uplink RLC PDU and the second part of uplink RLC PDU, a situation may occur in which retransmission is required due to a communication condition, and the process of data retransmission will be described in detail with reference to fig. 18 and 19.

Fig. 18 is a schematic flow chart of an uplink data retransmission process according to an embodiment of the present invention. In fig. 18, a retransmission procedure of an uplink RLC PDU for the RLC AM in fig. 17 will be described in detail.

1801, the macro base station receives the first part of uplink RLC PDU and the second part of uplink RLC PDU, and generates a second RLC status report according to the receiving status of the first part of uplink RLC PDU and the second part of uplink RLC PDU.

1802, the macro base station sends a second RLC status report to the UE.

And 1803, the UE determines an uplink retransmission set according to the second RLC state report. The uplink retransmission set comprises the RLC PDU which needs to be retransmitted in the first part of uplink RLC PDU and/or the RLC PDU which needs to be retransmitted in the second part of uplink RLC PDU.

The UE may update the RLC AM transmission window and the corresponding state variables to continue transmitting new RLC PDUs according to the second RLC status report when the second RLC status report indicates that the macro base station acknowledges the successful RLC PDUs.

The UE may divide the uplink retransmission set into a first uplink retransmission subset and a second uplink retransmission subset according to the first uplink grant information of the PCell and/or the second uplink grant information on the SCell, and determine to retransmit the first uplink retransmission subset to the macro base station and retransmit the second uplink retransmission subset to the micro base station.

The ue retransmits 1804 the RLC PDU of the first uplink retransmission subset to the macro base station.

1805, the ue retransmits RLC PDUs of the second uplink retransmission subset to the micro base station.

Fig. 19 is a schematic flow chart of an uplink data retransmission process according to an embodiment of the present invention. In fig. 19, a retransmission procedure of an uplink RLC PDU for the RLC AM in fig. 17 will be described in detail.

Steps 1901 to 1903 in fig. 19 are similar to steps 1801 to 1803 in fig. 18, and are not repeated here.

1904, the ue sends RLC PDU of the uplink retransmission set to the macro base station.

The UE may determine to retransmit all uplink RLC PDUs that need to be retransmitted to the macro base station according to the first uplink grant information of the PCell and/or the second uplink grant information on the SCell.

Fig. 20 is a schematic flow chart of an uplink data retransmission process according to an embodiment of the present invention. In fig. 20, a retransmission procedure of an uplink RLC PDU for the RLC AM in fig. 17 will be described in detail.

Steps 2001 to 2003 in fig. 20 are similar to steps 1801 to 1803 in fig. 18, and are not repeated here.

2004, the ue sends RLC PDUs of the uplink retransmission set to the micro base station.

The UE may determine to retransmit all uplink RLC PDUs that need to be retransmitted to the micro base station according to the first uplink grant information of the PCell and/or the second uplink grant information on the SCell.

2005, the micro base station transmits RLC PDU of the uplink retransmission set to the macro base station.

The micro base station may send uplink RLC PDUs requiring retransmission to the macro base station through an X2 interface or a direct connection.

In fig. 21, the first base station may be one of a macro base station and a micro base station, and the second base station may be the other base station.

2101, the ue sends an RRC connection re-establishment request message to the macro base station.

In the case of RLC PDU retransmission maximum number or PCell RLM judging radio link failure (Radio Link Failure, RLF) or random access procedure failure or RRC connection reconfiguration failure or integrity check failure or handover failure on the PCell, the UE may perform cell selection, and still select the PCell in the case of good PCell radio conditions. Then, the UE sends an RRC connection re-establishment request message to the macro base station and initiates an RRC connection re-establishment procedure including suspending (suspend) all RBs except SRB0, resetting the MAC, using a default physical channel configuration, using a default MAC layer master configuration (MAC main configuration), etc. Unlike the prior art, the SCell provided by the micro base station may not be released at RRC connection reestablishment.

2102, the macro base station sends a re-establishment notification message to the micro base station.

The reestablishment notification message may include DRB-related parameters and may instruct the micro base station to suspend the shunted DRBs.

2103, the micro base station suspends the distributed DRBs according to the reestablishment notification message, and reconfigures the relevant parameters of the DRBs.

2104, the macro base station sends an RRC connection reestablishment (RRCConnectionReestablishment) message to the UE.

2105, the ue reestablishes PDCP entity and RLC entity of SRB1, performs radio resource configuration procedure, and recovers SRB1, etc., according to the RRC connection reestablishment message.

2106, the ue sends an RRC connection reestablishment complete (rrcconnectionreestablishfabric) message to the macro base station.

2107, the macro base station sends an RRC connection reestablishment complete message to the micro base station.

It should be understood that the sequence numbers of the above processes do not mean the order of execution, and the execution order of the processes should be determined by the functions and internal logic of the processes, and should not be construed as limiting the implementation process of the embodiments of the present invention. For example, step 2102 may be performed in parallel with steps 2103 through 2104, or steps 2103 and 2104 may be performed first, followed by step 2102.

Fig. 22 is a schematic block diagram of a base station according to an embodiment of the present invention. The base station 2200 of fig. 22 is the first base station described above. Base station 2200 includes generation unit 2201 and transmission unit 2202.

The generating unit 2201 generates RLC PDU. The transmitting unit 2202 transmits a first part of downlink RLC PDUs among the downlink RLC PDUs to the UE, and transmits a second part of downlink RLC PDUs among the downlink RLC PDUs to the second base station, so that the second base station transmits the second part of downlink RLC PDUs to the UE.

In the embodiment of the invention, the first part of downlink RLC PDU in the downlink RLC PDU is sent to the UE, and the second part of downlink RLC PDU in the downlink RLC PDU is sent to the second base station, so that the two base stations can jointly send data to the UE, thereby improving the peak rate and throughput of the UE.

The other operations and functions of the base station 2200 may refer to the procedure related to the first base station in the method embodiments of fig. 2a to 21 above, and in order to avoid repetition, a description thereof will be omitted.

Alternatively, as another embodiment, the base station 2200 may further include a first receiving unit 2203.

The first receiving unit 2203 may receive a first part of uplink RLC PDUs among uplink RLC PDUs generated by the UE from the UE, and receive a second part of uplink RLC PDUs among the uplink RLC PDUs from the second base station, wherein the second part of uplink RLC PDUs is received from the UE by the second base station.

Optionally, as another embodiment, the base station 2200 may further comprise a second receiving unit 2204. The second receiving unit 2204 may receive the first RLC status report from the UE. The transmitting unit 2202 may retransmit the RLC PDU requiring retransmission from the first part of downlink RLC PDUs to the UE when the first RLC status report indicates the RLC PDU requiring retransmission from the first part of downlink RLC PDUs.

The sending unit 2202 may further forward a first RLC status report to the second base station, where the first RLC status report indicates an RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs or send a retransmission message generated by the first base station according to the first RLC status report to the second base station, where the retransmission message indicates an RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs.

Alternatively, as another embodiment, the base station 2200 may further include a third receiving unit 2205 and a first determining unit 2206.

The third receiving unit 2205 may receive a first RLC status report from the second base station, wherein the first RLC status report is received by the second base station from the UE.

The first determining unit 2206 may determine, according to the first RLC status report, an RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs;

the transmitting unit 2202 may also retransmit RLC PDUs that need to be retransmitted from among the first portion of downlink RLC PDUs to the UE.

Optionally, as another embodiment, the base station 2200 may further comprise a fourth receiving unit 2207.

The generating unit 2201 may further generate a second RLC status report according to the reception status of the first part of uplink RLC PDU and the second part of uplink RLC PDU. The transmission unit 2202 may also transmit a second RLC status report to the UE.

The fourth receiving unit 2207 may receive RLC PDUs of an uplink retransmission set determined by the UE according to the second RLC status report, where the uplink retransmission set includes RLC PDUs required to be retransmitted in the first portion of uplink RLC PDUs and/or RLC PDUs required to be retransmitted in the second portion of uplink RLC PDUs.

Alternatively, as another embodiment, the fourth receiving unit 2207 may receive RLC PDUs of the uplink retransmission set from the UE; or receiving RLC PDUs of the first uplink retransmission subset from the UE, and receiving RLC PDUs of the second uplink retransmission subset from the second base station, where the RLC PDUs of the second uplink retransmission subset are received by the second base station from the UE, and the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission subset by the UE; or receiving RLC PDUs of an uplink retransmission set from the second base station, the RLC PDUs of the uplink retransmission set being received from the UE by the second base station.

Alternatively, as another embodiment, the sending unit 2202 may send the first part of the downlink RLC PDU to the UE on the first cell of the base station 2200 and send the second part of the downlink RLC PDU to the second base station, so that the second base station sends the second part of the downlink RLC PDU to the UE on the second cell of the second base station, where the coverage area of the first cell and the second cell overlap.

Alternatively, as another example, the base station 2200 may further comprise a fifth receiving unit 2208,

the sending unit 2202 may also send a first request message to the second base station, where the first request message is used to instruct the second base station to configure the second cell for the UE.

The fifth receiving unit 2208 may receive a first response message from the second base station, where the first response message carries resource information of the second cell determined by the second base station according to the first request message.

The sending unit 2202 may also send a radio resource control, RRC, connection reconfiguration message to the UE, the RRC connection reconfiguration message carrying resource information of the second cell.

Alternatively, as another embodiment, the base station 2200 may further include a sixth receiving unit 2209 and a second determining unit 2210.

The sixth receiving unit 2209 may receive a second request message from the second base station, the second request message being used to instruct the base station 2200 to configure the first cell for the UE.

The second determination unit 2210 may determine the resource information of the first cell according to the second request message.

The sending unit 2201 may further send a second response message to the second base station, where the second response message carries the resource information of the first cell, so that the second base station notifies the UE of the resource information of the first cell.

Alternatively, as another embodiment, the base station 2200 may further comprise a setup unit 2211.

The second request message may also be used to instruct the base station to establish a DRB for the UE, and the establishing unit 2211 may establish a PDCP entity, an RLC entity, and a logical channel corresponding to the DRB according to the second request message.

Alternatively, as another embodiment, the second request message may also be used to indicate that the base station 2200 is responsible for data offloading.

The sending unit 2202 may also send a path switching request message to the MME according to the second request message, so that the MME requests to switch the data transmission path to the serving gateway to the path of the base station 2200 according to the path switching request message.

Alternatively, the first receiving unit to the sixth receiving unit may be the same receiving unit or the same receiving unit. For example, the actions of the first receiving unit to the sixth receiving unit may be performed by one receiver.

Fig. 23 is a schematic block diagram of a base station according to an embodiment of the present invention. The base station 2300 is the second base station described above. Base station 2300 includes a receiving unit 2310 and a transmitting unit 2320.

The receiving unit 2310 receives a second part of the downlink RLC PDUs generated by the first base station from the first base station. The transmitting unit 2320 transmits the second portion of the downlink RLC PDU to the UE.

In the embodiment of the invention, the peak rate and throughput of the UE can be improved by sending the second part of downlink RLC PDUs in the downlink RLC PDUs generated by the first base station to the UE.

The other functions and operations of the base station 2300 may refer to the procedure related to the second base station in the method embodiments of fig. 2a to 21, and are not repeated here to avoid repetition.

Alternatively, as another embodiment, the receiving unit 2310 may also receive a second part of the UE-generated uplink RLC PDU from the UE. The transmitting unit 2320 may also transmit a second portion of the uplink RLC PDU to the first base station.

Alternatively, as another embodiment, the base station 2300 may further include a first determination unit 2330.

The receiving unit 2310 may receive the first RLC status report from the first base station, the first determining unit 2330 may determine, according to the first RLC status report, an RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs, and the transmitting unit 2320 may retransmit the RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs to the UE.

Alternatively, the receiving unit 2310 may further receive a retransmission message from the first base station, and the transmitting unit 2320 may further retransmit RLC PDUs required to be retransmitted in the second portion of downlink RLC PDUs to the UE according to the retransmission message, where the first retransmission message indicates RLC PDUs required to be retransmitted in the second portion of downlink RLC PDUs.

Alternatively, as another embodiment, the receiving unit 2310 may also receive the first RLC status report from the UE. The sending unit 2320 may further forward the first RLC status report to the first base station, so that when the first RLC status report indicates an RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs, the first base station may retransmit the RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs to the UE. The sending unit 2320 may further retransmit the RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs to the UE when the first RLC status report indicates the RLC PDU that needs to be retransmitted in the second portion of downlink RLC PDUs.

Optionally, as another embodiment, the receiving unit 2310 may further receive RLC PDUs of an uplink retransmission set from the UE, and the sending unit 2320 may further send RLC PDUs of the uplink retransmission set to the first base station, where the uplink retransmission set includes RLC PDUs requiring retransmission in the first portion of uplink RLC PDUs and/or RLC PDUs requiring retransmission in the second portion of uplink RLC PDUs.

Alternatively, the receiving unit 2310 may further receive RLC PDUs of a second uplink retransmission subset from the UE, and the transmitting unit 2320 may further transmit RLC PDUs of the second uplink retransmission subset to the first base station, where the second uplink retransmission subset is obtained by dividing the uplink retransmission set by the UE.

Alternatively, as another embodiment, the transmitting unit 2320 may transmit the second portion of the downlink RLC PDU to the UE on the second cell of the base station 2300.

Alternatively, as another embodiment, the base station 2300 may further include a second determination unit 2340. The receiving unit 2340 may also receive a first request message from the first base station, the first request message being for instructing the base station to configure the second cell for the UE.

The second determining unit 2340 may determine resource information of the second cell according to the first request message.

The transmitting unit 2320 may further transmit a first response message to the first base station, where the first response message carries resource information of the second cell, so that the first base station notifies the UE of the resource information of the second cell.

Alternatively, as another embodiment, the base station 2300 may further include a setup unit 2350.

The first request message may also be used to instruct the base station 2300 to establish a DRB for the UE. The establishing unit 2350 may establish RLC entities and logical channels corresponding to the DRBs according to the first request message.

Optionally, as another embodiment, the sending unit 2320 may further send a second request message to the first base station, where the second request message is used to instruct the first base station to configure the first cell of the first base station for the UE. The receiving unit 2310 may also receive a second response message from the first base station, where the second response message carries resource information of the first cell determined by the first base station according to the second request message. The sending unit 2320 may also send a radio resource control RRC connection reconfiguration message to the UE, where the RRC connection reconfiguration message carries resource information of the first cell.

Optionally, as another embodiment, the second request message is further used to instruct the first base station to establish a DRB for the UE.

Fig. 24 is a schematic block diagram of a UE according to an embodiment of the present invention. The UE 2400 includes a receiving unit 2410 and a first generating unit 2420.

The receiving unit 2410 receives a first part of downlink RLC PDUs among the downlink RLC PDUs generated by the first base station from the first base station, and receives a second part of downlink RLC PDUs among the downlink RLC PDUs from the second base station, wherein the second part of downlink RLC PDUs is received from the first base station by the second base station. The first generation unit 2420 reassembles the first portion of downlink RLC PDU and the second portion of downlink RLC PDU to form a downlink RLC SDU.

Other functions and operations of the UE 2400 may refer to the procedure related to the UE in the method embodiments of fig. 2a to 21 above, and are not repeated here to avoid repetition.

Optionally, as another embodiment, the UE 2400 may further include a first transmission unit 2430. The first generation unit 2420 may generate an uplink RLC PDU. The first transmission unit 2440 may transmit a first part of the uplink RLC PDUs to the first base station and a second part of the uplink RLC PDUs to the second base station.

Alternatively, as another embodiment, the UE 2400 may further include a second generating unit 2440 and a second transmitting unit 2450.

The second generating unit 2440 may generate a first RLC status report according to the receiving conditions of the first part of downlink RLC PDU and the second part of downlink RLC PDU, where the first RLC status report indicates an RLC PDU that needs to be retransmitted in the first part of downlink RLC PDU and/or an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDU.

The second transmission unit 2450 may transmit the first RLC status report to the first base station or the second base station.

The receiving unit 2410 may also receive RLC PDUs requiring retransmission from the first base station in the first part of downlink RLC PDUs and/or RLC PDUs requiring retransmission from the second base station in the second part of downlink RLC PDUs.

Alternatively, as another embodiment, the UE 2400 may further include a determining unit 2460 and a third transmitting unit 2470.

The receiving unit 2410 may also receive a second RLC status report from the first base station.

The determining unit 2460 may determine an uplink retransmission set according to the second RLC status report, where the uplink retransmission set includes RLC PDUs requiring retransmission in the first portion of uplink RLC PDUs and/or RLC PDUs requiring retransmission in the second portion of uplink RLC PDUs.

The third sending unit 2470 may send RLC PDUs of the uplink retransmission set to the first base station, or send RLC PDUs of the uplink retransmission set to the second base station, or send RLC PDUs of the first uplink retransmission subset to the first base station and RLC PDUs of the second uplink retransmission subset to the second base station, where the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission set by the UE.

Alternatively, as another embodiment, the receiving unit 2410 may receive a first portion of the downlink RLC PDU from a first cell of a first base station and a second portion of the downlink RLC PDU from a second cell of a second base station, where coverage areas of the first cell and the second cell overlap.

Alternatively, as another embodiment, the receiving unit 2410 may further receive a radio resource control RRC connection reconfiguration message from the first base station, where the RRC connection reconfiguration message carries resource information of the second cell determined by the second base station.

Alternatively, as another embodiment, the receiving unit 2410 may further receive an RRC connection reconfiguration message from the second base station, where the RRC connection reconfiguration message carries the resource information of the first cell determined by the first base station.

Alternatively, the first to third sending units may be the same sending unit or the same sending unit. For example, the actions of the first transmitting unit to the third transmitting unit may be performed by one transmitter.

Fig. 25 is a schematic block diagram of a base station according to an embodiment of the present invention. The base station 2500 in fig. 25 is the first base station described above. Base station 2500 includes a processor 2510 and a transmitter 2520.

The processor 2510 generates RLC PDUs. The transmitter 2520 transmits a first portion of the downlink RLC PDUs to the UE and a second portion of the downlink RLC PDUs to the second base station, so that the second base station transmits the second portion of the downlink RLC PDUs to the UE.

The other operations and functions of the base station 2500 may refer to the procedure related to the first base station in the method embodiments of fig. 2a to 21, and are not repeated here for avoiding repetition.

Optionally, as another embodiment, the base station 2500 may further comprise a receiver 2530.

The receiver 2530 may receive a first portion of uplink RLC PDUs from the UE, and a second portion of uplink RLC PDUs from the second base station, from among the uplink RLC PDUs generated by the UE.

Alternatively, as another embodiment, the receiver 2530 may receive the first RLC status report from the UE. The transmitter 2520 may retransmit the RLC PDU of the first portion of downlink RLC PDUs that needs to be retransmitted to the UE when the first RLC status report indicates the RLC PDU of the first portion of downlink RLC PDUs that needs to be retransmitted.

The transmitter 2520 may also forward a first RLC status report to the second base station, where the first RLC status report indicates RLC PDUs that need to be retransmitted in the second portion of downlink RLC PDUs, or send a retransmission message to the second base station, where the retransmission message indicates RLC PDUs that need to be retransmitted in the second portion of downlink RLC PDUs, where the retransmission message is generated by the first base station according to the first RLC status report.

Alternatively, as another embodiment, the receiver 2530 may receive a first RLC status report from a second base station, wherein the first RLC status report is received by the second base station from the UE.

The processor 2510 may determine, according to the first RLC status report, an RLC PDU that needs to be retransmitted in the first portion of downlink RLC PDUs;

the transmitter 2520 may also retransmit RLC PDUs requiring retransmission from the first portion of downlink RLC PDUs to the UE.

Optionally, as another embodiment, the processor 2510 may further generate a second RLC status report according to the reception status of the first portion uplink RLC PDU and the second portion uplink RLC PDU. The transmitter 2520 may also send a second RLC status report to the UE.

The receiver 2530 may receive RLC PDUs of an uplink retransmission set determined by the UE according to the second RLC status report, where the uplink retransmission set includes RLC PDUs requiring retransmission in the first portion of uplink RLC PDUs and/or RLC PDUs requiring retransmission in the second portion of uplink RLC PDUs.

Alternatively, as another embodiment, the receiver 2530 may receive RLC PDUs of the uplink retransmission set from the UE; or receiving RLC PDUs of the first uplink retransmission subset from the UE, and receiving RLC PDUs of the second uplink retransmission subset from the second base station, where the RLC PDUs of the second uplink retransmission subset are received by the second base station from the UE, and the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission subset by the UE; or receiving RLC PDUs of an uplink retransmission set from the second base station, the RLC PDUs of the uplink retransmission set being received from the UE by the second base station.

Alternatively, as another embodiment, the transmitter 2520 may send a first portion of the downlink RLC PDUs to the UE on a first cell of the base station 2500 and a second portion of the downlink RLC PDUs to a second base station, such that the second portion of the downlink RLC PDUs is sent by the second base station to the UE on a second cell of the second base station, wherein the coverage of the first cell and the second cell overlap.

Optionally, as another embodiment, the transmitter 2520 may further send a first request message to the second base station, where the first request message is used to instruct the second base station to configure the second cell for the UE.

The receiver 2530 may receive a first response message from the second base station, where the first response message carries resource information of the second cell determined by the second base station according to the first request message.

The transmitter 2520 may also send a radio resource control, RRC, connection reconfiguration message to the UE, the RRC connection reconfiguration message carrying resource information of the second cell.

Alternatively, as another embodiment, the receiver 2530 may receive a second request message from the second base station, where the second request message is used to instruct the base station 2500 to configure the first cell for the UE.

Processor 2510 can determine resource information for the first cell based on the second request message.

The transmitter 2520 may also send a second response message to the second base station, the second response message carrying the resource information of the first cell, so that the second base station informs the UE of the resource information of the first cell.

Optionally, as another embodiment, the second request message may be further used to instruct the base station to establish a DRB for the UE. The processor 2510 may establish PDCP entities, RLC entities, and logical channels corresponding to the DRBs according to the second request message.

The transmitter 2520 may also send a path switch request message to the MME according to the second request message, such that the MME requests to the serving gateway to switch the data transmission path to the serving gateway to base station 2500 path according to the path switch request message.

Fig. 26 is a schematic block diagram of a base station according to an embodiment of the present invention. The base station 2600 is the second base station described above. Base station 2600 includes a receiver 2610 and a transmitter 2620.

The receiver 2610 receives, from the first base station, a second part of downlink RLC PDUs generated by the first base station. The transmitter 2620 transmits the second part of the downlink RLC PDU to the UE.

The other functions and operations of the base station 2600 may refer to the procedure related to the second base station in the method embodiments of fig. 2a to 21, and are not repeated here for avoiding repetition.

Optionally, as another embodiment, the receiver 2610 may further receive a second part of the UE-generated uplink RLC PDU from the UE. The transmitter 2620 may also transmit a second portion of the uplink RLC PDU to the first base station.

Optionally, as another embodiment, the base station 2600 may further include a processor 2630. The receiver 2610 may receive the first RLC status report from the first base station, the processor 2630 may determine, according to the first RLC status report, RLC PDUs requiring retransmission in the second portion of downlink RLC PDUs, and the transmitter 2620 may further retransmit, to the UE, RLC PDUs requiring retransmission in the second portion of downlink RLC PDUs.

Alternatively, the receiver 2610 may further receive a retransmission message from the first base station, and the transmitter 2620 may further retransmit RLC PDUs requiring retransmission in the second part of downlink RLC PDUs to the UE according to the retransmission message, where the first retransmission message indicates RLC PDUs requiring retransmission in the second part of downlink RLC PDUs.

Optionally, as another embodiment, the receiver 2610 may also receive the first RLC status report from the UE. The transmitter 2620 may further forward a first RLC status report to the first base station for retransmitting the RLC PDU of the first portion of downlink RLC PDUs that needs to be retransmitted to the UE when the first RLC status report indicates the RLC PDU of the first portion of downlink RLC PDUs that needs to be retransmitted. The transmitter 2620 may further retransmit the RLC PDU requiring retransmission from the second portion of downlink RLC PDUs to the UE when the first RLC status report indicates the RLC PDU requiring retransmission from the second portion of downlink RLC PDUs.

Optionally, as another embodiment, the receiver 2610 may further receive RLC PDUs of an uplink retransmission set from the UE, and the transmitter 2620 may further send RLC PDUs of the uplink retransmission set to the first base station, where the uplink retransmission set includes RLC PDUs requiring retransmission in the first part of uplink RLC PDUs and/or RLC PDUs requiring retransmission in the second part of uplink RLC PDUs.

Alternatively, the receiver 2610 may further receive RLC PDUs of a second uplink retransmission subset from the UE, and the transmitter 2620 may further transmit RLC PDUs of the second uplink retransmission subset to the first base station, where the second uplink retransmission subset is obtained by dividing the uplink retransmission set by the UE.

Alternatively, as another embodiment, the transmitter 2620 may transmit a second portion of the downlink RLC PDU to the UE on a second cell of the base station 2600.

Optionally, as another embodiment, the receiver 2610 may further receive a first request message from the first base station, where the first request message may be used to instruct the base station to configure the second cell for the UE.

The processor 2630 may determine resource information of the second cell according to the first request message.

The transmitter 2620 may further transmit a first response message to the first base station, the first response message carrying resource information of the second cell, so that the first base station informs the UE of the resource information of the second cell.

Optionally, as another embodiment, the first request message may also be used to instruct the base station 2600 to establish a DRB for the UE. The processor 2630 may establish RLC entities and logical channels corresponding to the DRBs according to the first request message.

Optionally, as another embodiment, the transmitter 2620 may further send a second request message to the first base station, where the second request message is used to instruct the first base station to configure the first cell of the first base station for the UE. The receiver 2610 may also receive a second response message from the first base station, the second response message carrying resource information of the first cell determined by the first base station according to the second request message. The transmitter 2620 may also send a radio resource control, RRC, connection reconfiguration message to the UE, the RRC connection reconfiguration message carrying resource information of the first cell.

Fig. 27 is a schematic block diagram of a UE according to an embodiment of the present invention. UE 2700 includes receiver 2710 and processor 2720.

The receiver 2710 receives a first portion of downlink RLC PDUs from a first base station among downlink RLC PDUs generated by the first base station, and receives a second portion of downlink RLC PDUs from a second base station, wherein the second portion of downlink RLC PDUs is received by the second base station from the first base station. Processor 2720 reassembles the first portion of downlink RLC PDU and the second portion of downlink RLC PDU to form a downlink RLC SDU.

Other functions and operations of the UE 2700 may refer to the procedure related to the UE in the method embodiments of fig. 2a to 21 above, and are not repeated here to avoid repetition.

Optionally, as another embodiment, the UE 2400 may further include a transmitter 2730. Processor 2720 may generate an uplink RLC PDU. The transmitter 2730 may transmit a first portion of the uplink RLC PDUs to the first base station and a second portion of the uplink RLC PDUs to the second base station.

Alternatively, as another embodiment, the processor 2720 may generate a first RLC status report according to the receiving conditions of the first part of downlink RLC PDUs and the second part of downlink RLC PDUs, where the first RLC status report indicates an RLC PDU that needs to be retransmitted in the first part of downlink RLC PDUs and/or an RLC PDU that needs to be retransmitted in the second part of downlink RLC PDUs.

The transmitter 2730 may send a first RLC status report to the first base station or the second base station.

The receiver 2710 may also receive RLC PDUs requiring retransmission from the first base station in the first portion of downlink RLC PDUs and/or RLC PDUs requiring retransmission from the second base station in the second portion of downlink RLC PDUs.

Alternatively, as another embodiment, the receiver 2710 may also receive a second RLC status report from the first base station.

Processor 2720 may determine an uplink retransmission set according to the second RLC status report, where the uplink retransmission set includes RLC PDUs requiring retransmission in the first portion of uplink RLC PDUs and/or RLC PDUs requiring retransmission in the second portion of uplink RLC PDUs.

The transmitter 2730 may send RLC PDUs of the uplink retransmission set to the first base station, or RLC PDUs of the uplink retransmission set to the second base station, or RLC PDUs of the first uplink retransmission subset to the first base station and RLC PDUs of the second uplink retransmission subset to the second base station, where the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission set by the UE.

Alternatively, as another embodiment, the receiver 2710 may receive a first portion of downlink RLC PDUs from a first cell of a first base station and a second portion of downlink RLC PDUs from a second cell of a second base station, where coverage areas of the first cell and the second cell overlap.

Optionally, as another embodiment, the receiver 2710 may further receive a radio resource control RRC connection reconfiguration message from the first base station, where the RRC connection reconfiguration message carries resource information of the second cell determined by the second base station.

Optionally, as another embodiment, the receiver 2710 may further receive an RRC connection reconfiguration message from the second base station, where the RRC connection reconfiguration message carries resource information of the first cell determined by the first base station.

In the embodiment of the invention, the peak rate and throughput of the UE can be improved by the UE receiving a first part of downlink RLC PDU in the downlink RLC PDU from the first base station and receiving a second part of downlink RLC PDU acquired from the first base station by the second base station from the second base station.

Fig. 28 is a schematic block diagram of a base station according to an embodiment of the present invention. The base station 2800 of fig. 28 may be the first base station described above. Base station 2800 includes a receiving unit 2810 and a reassembling unit 2820.

The receiving unit 2810 receives a first part of uplink RLC PDUs from the UE, and a second part of uplink RLC PDUs from the second base station, from among the uplink RLC PDUs generated by the UE. The reassembly unit 2820 reassembles the first and second portions of uplink RLC PDUs.

In the embodiment of the invention, the two base stations can jointly transmit data with the UE by receiving the first part of uplink RLC PDU in the uplink RLC PDU generated by the UE from the UE and receiving the second part of uplink RLC PDU in the uplink RLC PDU from the second base station, so that the peak rate and throughput of the UE can be improved.

Additional functions and operations of the base station 2800 may be referred to the procedure of the method embodiment of fig. 2b above, and will not be repeated here.

Optionally, as an embodiment, the base station may further include a generating unit 2830 and a transmitting unit 2840. The generating unit 2830 may generate the second RLC status report according to the reception status of the first part of uplink RLC PDU and the second part of uplink RLC PDU. The transmitting unit 2840 may transmit the second RLC status report to the UE. The receiving unit 2810 may receive RLC PDUs of an uplink retransmission set determined by the UE according to the second RLC status report, where the uplink retransmission set includes RLC PDUs required to be retransmitted in the first part of uplink RLC PDUs and/or RLC PDUs required to be retransmitted in the second part of uplink RLC PDUs.

Alternatively, as another embodiment, the receiving unit 2810 may receive RLC PDUs of the uplink retransmission set from the UE. Alternatively, the receiving unit 2810 may receive RLC PDUs of a first uplink retransmission subset from the UE and RLC PDUs of a second uplink retransmission subset from the second base station, where the RLC PDUs of the second uplink retransmission subset are received by the second base station from the UE, and the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission subset by the UE. Alternatively, the receiving unit 2810 may receive RLC PDUs of an uplink retransmission set from the second base station, which RLC PDUs are received from the UE by the second base station.

Fig. 29 is a schematic block diagram of a base station according to an embodiment of the present invention. The base station 2900 of fig. 29 may be the second base station described above. Base station 2900 includes a receiving unit 2910 and a transmitting unit 2920.

The receiving unit 2910 receives, from the UE, a second part of uplink RLC PDUs among the uplink RLC PDUs generated by the UE. The transmitting unit 2920 transmits the second part of the uplink RLC PDU to the first base station.

In the embodiment of the invention, the peak rate and throughput of the UE can be improved by sending the second part of uplink RLC PDUs in the uplink RLC PDUs generated by the UE to the first base station.

Optionally, as an embodiment, the receiving unit 2910 may further receive RLC PDUs of an uplink retransmission set from the UE. The sending unit 2920 may further send RLC PDUs of an uplink retransmission set to the first base station, where the uplink retransmission set includes RLC PDUs that need to be retransmitted in the first part of uplink RLC PDUs and/or RLC PDUs that need to be retransmitted in the second part of uplink RLC PDUs. Alternatively, the receiving unit 2910 may receive RLC PDUs of a second uplink retransmission subset from the UE, and send RLC PDUs of the second uplink retransmission subset to the first base station, where the second uplink retransmission subset is obtained by dividing the uplink retransmission set by the UE.

Fig. 30 is a schematic block diagram of a UE according to an embodiment of the present invention. The UE 3000 includes a generating unit 3010 and a transmitting unit 3020.

The generation unit 3010 generates uplink RLC PDUs. The transmitting unit 3020 transmits a first part of uplink RLC PDUs among the uplink RLC PDUs to the first base station, and transmits a second part of uplink RLC PDUs among the uplink RLC PDUs to the second base station, so that the second base station transmits the second part of uplink RLC PDUs to the first base station.

In the embodiment of the invention, the UE transmits the first part of uplink RLC PDU to the first base station, and transmits the second part of uplink RLC PDU to the second base station, and the second base station transmits the second part of uplink RLC PDU to the first base station, so that the UE can transmit data together with the two base stations, thereby improving the peak rate and throughput of the UE.

Optionally, as an embodiment, the UE 3000 may further include a receiving unit 3030 and a determining unit 3040. The receiving unit 3030 may receive a second RLC status report from the first base station. The determining unit 3040 may determine an uplink retransmission set according to the second RLC status report, where the uplink retransmission set includes RLC PDUs requiring retransmission in the first portion of uplink RLC PDUs and/or RLC PDUs requiring retransmission in the second portion of uplink RLC PDUs. The sending unit 3020 may further send RLC PDUs of the uplink retransmission set to the first base station, or send RLC PDUs of the uplink retransmission set to the second base station, or send RLC PDUs of the first uplink retransmission subset to the first base station and RLC PDUs of the second uplink retransmission subset to the second base station, where the first uplink retransmission subset and the second uplink retransmission subset are obtained by dividing the uplink retransmission set by the UE.

In the case of inter-base station CA, the UE may transmit data with each base station on the cells aggregated by each base station. When the UE traffic decreases or the radio conditions of cells aggregated therein become poor, the UE also needs to monitor the channels of these cells, which may result in waste of UE power. The embodiment of the invention provides a method for managing cell resources.

Fig. 31 is a schematic flow chart diagram of a method of cell resource management according to an embodiment of the invention. The method of fig. 31 is performed by a base station.

3110 the first base station determining activation time or deactivation time of a second cell of the second base station, where the first base station is a primary base station and the second base station is a secondary base station.

The first base station is a primary base station, the second base station is a secondary base station, and then the second cell of the second base station is an SCell. For example, the first base station may be a macro base station and the second base station may be a micro base station.

The indication signaling may be an activation signaling when the indication signaling indicates an activation time of the second cell. The indication signaling may be deactivation signaling when the indication signaling indicates a deactivation time of the second cell. For example, the activation signaling and the deactivation signaling may be MAC CEs (Control elements).

3120, the first base station informs the second base station and the UE of an activation time or a deactivation time of the second cell, respectively.

Alternatively, as another embodiment, the first base station sends indication signaling to the second base station and the UE, respectively, where the indication signaling may be used to indicate the activation time or the deactivation time of the second cell.

Alternatively, as another embodiment, the first base station may send indication signaling to the second base station, so that the second base station sends the indication signaling to the UE, and the indication signaling may be used to indicate the activation time or the deactivation time of the second cell.

It should be noted that before the deactivation time arrives, the second base station may transmit the RLC PDU or the RLC PDU not acknowledged in the RLC transmission buffer of the second cell, the RLC PDU in the RLC reception buffer to the first base station, or notify the SN of the RLC PDU to the first base station.

In the embodiment of the invention, the activation time or the deactivation time of the second cell of the second base station is determined through the first base station, and the activation time or the deactivation time of the second cell is notified to the UE, so that the UE can activate or deactivate the second cell, and the electric quantity of the UE can be saved.

In addition, the first base station informs the second base station and the UE of the activation time or the deactivation time of the second cell respectively, so that the consistency of the effective time of activation or deactivation between the second base station and the UE can be ensured, and the delay of the first base station and the second base station for transmitting the indication signaling at the X2 interface can be solved.

Fig. 32 is a schematic flow chart diagram of a method of cell resource management according to an embodiment of the invention. The method of fig. 32 is performed by a UE.

3210, the ue receives an indication signaling from the first base station or the second base station, where the indication signaling may be used to indicate an activation time or a deactivation time of a second cell of the second base station, where the first base station is a primary base station, the second base station is a secondary base station, and the activation time or the deactivation time of the second cell is determined by the first base station.

3220, the UE performs an activation operation on the second cell when the activation time arrives, or the UE performs a deactivation operation on the second cell when the deactivation time arrives.

In the embodiment of the invention, the UE receives the indication signaling from the first base station, so that the UE can activate or deactivate the second cell according to the indication signaling, thereby saving the electric quantity of the UE.

Fig. 33 is a schematic flow chart diagram of a method of cell resource management according to an embodiment of the invention. The method of fig. 33 is performed by a base station.

3310, the second base station determines an activation time or a deactivation time of a second cell of the second base station.

3320, the second base station informs the activation time or deactivation time of the second cell to the first base station and the UE, respectively, wherein the first base station is a main base station, and the second base station is an auxiliary base station.

Alternatively, as another embodiment, the second base station sends indication signaling to the first base station and the UE, respectively, where the indication signaling may be used to indicate the activation time or the deactivation time of the second cell.

Alternatively, as another embodiment, the second base station may send an indication signaling to the first base station, so that the first base station sends the indication signaling to the UE, and the indication signaling may be used to indicate the activation time or the deactivation time of the second cell.

Alternatively, as another embodiment, before the deactivation time arrives, the second base station may send the unacknowledged RLC PDU or the unsent RLC PDU in the RLC transmission buffer, the RLC PDU in the RLC reception buffer of the second cell to the first base station, or notify the SN of the RLC PDU to the first base station.

In the embodiment of the invention, the activation time or the deactivation time of the second cell of the second base station is determined through the second base station, and the activation time or the deactivation time of the second cell is notified to the UE, so that the UE can activate or deactivate the second cell, thereby saving the electric quantity of the UE.

Fig. 34 is a schematic flow chart diagram of a method of cell resource management according to an embodiment of the invention. The method of fig. 34 is performed by a UE.

At 3410, the ue receives indication signaling from the second base station or the first base station, the indication signaling may be used to indicate an activation time or a deactivation time of a second cell of the second base station, wherein the first base station is a primary base station and the second base station is a secondary base station, and wherein the activation time or the deactivation time of the second cell is determined by the second base station.

3420 the UE performs an activation operation on the second cell when the activation time arrives or a deactivation operation on the second cell when the deactivation time arrives.

In addition, in another embodiment, the UE may also maintain a deactivation timer corresponding to the second cell of the second base station, deactivate the second cell of the second base station when the deactivation timer expires, and send indication signaling to the first base station and the second base station, the indication signaling may be used to indicate that the second cell has been deactivated. The first base station may be a primary base station and the second base station may be a secondary base station. The second base station may send the unacknowledged RLC PDU or the unsent RLC PDU in the RLC transmission buffer of the second cell, the RLC PDU in the RLC reception buffer, to the first base station after receiving the indication signaling, or notify the SN of the RLC PDU to the first base station.

The method of cell resource management will be described in detail below in connection with specific examples.

For example, assume that a first base station is a macro base station and a second base station is a micro base station. The macro base station is a main base station, and the micro base station is an auxiliary base station. Assuming that the micro base station provides two carriers CC1 and CC2, and corresponding serving cells are SCell1 and SCell2, the indication signaling for SCell1 and SCell2 may be sent to the UE through the PCell on the macro base station and the SCell1 or SCell2 in an active state. Assuming that PUCCH is configured on SCell1, SCell1 may be deactivated only after SCell2 is deactivated; when activated, SCell1 should also be activated first. In this case, SCell1 and SCell2 may also be activated or deactivated simultaneously.

After SCell2 is deactivated, RLC PDUs in RLC1, RLC2 shunted to the micro base station may all be mapped to be transmitted or received on SCell 1.

The protocol stack shown in fig. 10 is described below. After SCell1 of the micro base station is deactivated, for RLC AM, unacknowledged RLC PDUs in the transmission buffers of RLC1 and RLC2 of the micro base station need to be transmitted back to the macro base station, or SN of RLC PDU corresponding to the macro base station is indicated (an original RLC PDU needs to be reserved in the transmission buffer or retransmission buffer of the macro base station). For RLC UM, RLC PDUs which have not been transmitted in the transmission buffers of RLC1, RLC2 of the micro base station need to be transmitted back to the macro base station, or SN of RLC PDU corresponding to the macro base station (an original RLC PDU needs to be reserved in the transmission buffer or retransmission buffer of the macro base station). For RLC AM and RLC UM, RLC PDUs in RLC1, RLC2 reception buffers need to be transmitted to the macro base station.

After SCell1 of the micro base station is deactivated, RLC PDUs in RLC1, RLC2 of the macro base station are no longer sent to the micro base station. The first RLC status report of the UE received by the macro base station is not further sent to the micro base station.

In the prior art, the UE may report the difference information between the maximum transmission power of the nominal UE on the serving cell and the estimated transmission power on the UL-SCH for each active state to the serving base station through a power headroom report (Power Headroom Reporting, PHR), and may report the difference information between the maximum transmission power of the nominal UE on the primary serving cell (PCell) and the estimated transmission power of the UL-SCH and the physical uplink control channel (Physical Uplink Control Channel, PUCCH). In this way, the serving base station may perform uplink power control according to the PHR. In the case of CA between base stations, if cells aggregated by two base stations are configured with PUCCHs, and UEs are configured to transmit both the PUSCH and the PUCCH on the aggregated cells, no corresponding mechanism is currently available to implement uplink power control of the two base stations.

Fig. 35 is a schematic flow chart of an uplink power control method according to an embodiment of the present invention. The method of fig. 35 is performed by a UE.

3510, the ue generates an extended PHR including first type Power Headroom (PH) information and second type PH information of a first cell of the first base station, and first type PH information and second type PH information of a second cell of the second base station.

It should be noted that in the case of CA between base stations, the first base station may be a primary base station and the second base station may be a secondary base station. Then the first cell may be a PCell and the second cell may be an SCell. In addition, the first base station may be a secondary base station, and the second base station may be a primary base station. Then the first cell may be an SCell and the second cell may be a Pcell. The embodiment of the present invention is not limited thereto.

The PH may include a Type 1 (Type 1) PH and a Type 2 (Type 2) PH. The type 1PH may be equal to the maximum transmit power PCMAX, c configured by the UE on each active state serving cell minus its PUSCH transmit power, and may be expressed as equation (1):

type 1ph=pcmax, c-PUSCH transmit power (1)

Type 2PH may be equal to the maximum transmit power PCMAX, c configured on the serving cell, minus its PUCCH transmit power and PUSCH transmit power, and may be expressed as equation (2):

Type 2ph=pcmax, c-PUCCH transmit power-PUSCH transmit power (2)

In the embodiment of the present invention, the first type PH information may include a type 1PH, and the second type PH information may include a type 2PH.

It should be noted that when the first cell has uplink resources, the first type PH information of the first cell may further include a maximum transmission power of the first cell. When the second cell has uplink resources, the first type PH information of the second cell may further include a maximum transmission power of the second cell.

The conditions for triggering PHR by the UE may include PHR triggered by the downlink loss change exceeding a preset threshold, PHR triggered by the expiration of a periodic PHR timer, PHR triggered by the UE exceeding a preset threshold due to the change of a power management parameter (P-MPRc), etc.

3520, the ue sends the extended PHR to the first base station, so that the first base station sends the extended PHR to the second base station, and the first base station and the second base station perform uplink power control according to the extended PHR.

After generating the extended PHR, the UE may send the extended PHR to the first base station according to uplink resources of the first cell.

The first base station can send the extended PHR to the second base station through the X2 interface, and after the first base station and the second base station receive the extended PHR, the first base station and the second base station can control uplink power according to the extended PHR.

It should be noted that after the UE transmits the extended PHR, a inhibit PHR Timer (inhibit PHR-Timer) may be started or restarted, and the UE cannot transmit the extended PHR again when the inhibit PHR Timer is running. The length of the PHR prohibition timer is generally far longer than the delay of the X2 interface, so that the first base station or the second base station cannot continuously receive the extended PHR sent by the UE and the PHR forwarded by the other base station in a short time, and the ambiguity problem that the first base station or the second base station cannot easily judge which extended PHR is the latest exists.

In the embodiment of the invention, the extended PHR is generated by the UE, and the extended PHR comprises the PH information of the first cell of the first base station and the PH information of the second cell of the second base station, so that the UE transmits the extended PHR to the first base station, and the first base station transmits the extended PHR to the second base station, so that the first base station and the second base station can perform uplink power control according to the extended PHR.

Fig. 36 is a schematic flow chart diagram of an uplink power control method according to an embodiment of the present invention. The method of fig. 36 is performed by a base station.

3610, the first base station receives an extended PHR from the UE, the extended PHR including first type PH information and second type PH information of a first cell of the first base station, and first type PH information and second type PH information of a second cell of the second base station.

3620, the first base station performs uplink power control according to the extended PHR, and sends the extended PHR to the second base station, so that the second base station performs uplink power control according to the extended PHR.

In the embodiment of the invention, the first base station receives the extended PHR from the UE and sends the extended PHR to the second base station, and the extended PHR comprises the PH information of the first cell of the first base station and the PH information of the second cell of the second base station, so that the first base station and the second base station can both control uplink power according to the extended PHR.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

It will be clear to those skilled in the art that, for convenience and brevity of description, specific working procedures of the above-described systems, apparatuses and units may refer to corresponding procedures in the foregoing method embodiments, and are not repeated herein.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices, and methods may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present invention may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention may be embodied essentially or in a part contributing to the prior art or in a part of the technical solution, in the form of a software product stored in a storage medium, comprising several instructions for causing a computer device (which may be a personal computer, a server, a network device, etc.) to perform all or part of the steps of the method according to the embodiments of the present invention. And the aforementioned storage medium includes: a U-disk, a removable hard disk, a Read-Only Memory (ROM), a random access Memory (RAM, random Access Memory), a magnetic disk, or an optical disk, or other various media capable of storing program codes.

The foregoing is merely illustrative of the present invention, and the present invention is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A method of transmitting data, comprising:

the method comprises the steps that a first base station sends a request message to a second base station, wherein the request message is used for instructing the second base station to establish a Data Radio Bearer (DRB) for User Equipment (UE), and is also used for instructing the second base station to serve as a user plane anchor point;

the first base station receives a response message from the second base station, wherein the response message carries resource information of a cell of the second base station;

the first base station sends a Radio Resource Control (RRC) connection reconfiguration message to the UE, wherein the RRC connection reconfiguration message comprises resource information of a cell of the second base station;

the first base station receives downlink data of the UE from the second base station;

and the first base station sends the downlink data to the UE.

2. The method according to claim 1, wherein the method further comprises:

the first base station receives uplink data from the UE;

and the first base station sends the uplink data to the second base station.

3. The method according to claim 1 or 2, characterized in that the method further comprises:

the first base station receives a Radio Resource Control (RRC) connection reconfiguration completion message sent by the UE;

The first base station sends a configuration completion message to the second base station.

4. The method according to claim 1 or 2, characterized in that the request message is further used for instructing the second base station to establish a signaling radio bearer, SRB, for the UE.

5. The method according to claim 1 or 2, characterized in that the method further comprises:

the first base station receives a capacity allocation indication message sent by the second base station, wherein the capacity allocation indication message is used for indicating buffer information of data distribution transmission between the second base station and the first base station.

6. The method according to claim 1 or 2, characterized in that the method further comprises:

the first base station receives an extended power headroom report, PHR, comprising a first type power headroom, PH, and a second type PH of a first cell of the first base station, and a first type PH and a second type PH of a second cell of the second base station.

7. A method of transmitting data, comprising:

a second base station receives a request message from a first base station, wherein the request message is used for instructing the second base station to establish a Data Radio Bearer (DRB) for User Equipment (UE), and is also used for instructing the second base station to serve as a user plane anchor point;

The second base station sends a response message to the first base station, wherein the response message carries the resource information of the cell of the second base station;

the second base station receives downlink data of the UE from core network equipment;

and the second base station shunts the downlink data, sends the first part of the downlink data to the first base station, and sends the second part of the downlink data to the UE through a Uu interface.

8. The method of claim 7, wherein the method further comprises:

the second base station receiving a first portion of uplink data from the UE;

the second base station receiving a second portion of uplink data of the UE from the first base station;

the second base station sends the first part of the uplink data and the second part of the uplink data to the core network equipment.

9. The method according to claim 7 or 8, characterized in that the method further comprises:

the second base station receives a configuration completion message from the first base station.

10. The method according to claim 7 or 8, characterized in that the request message is further used for instructing the second base station to establish a signaling radio bearer, SRB, for the UE.

11. The method according to claim 7 or 8, characterized in that the method further comprises:

and the second base station sends a capacity allocation indication message to the first base station, wherein the capacity allocation indication message is used for indicating the buffer information of the second base station and the first base station for data stream transmission.

12. A method of transmitting data, comprising:

the User Equipment (UE) receives a Radio Resource Control (RRC) connection reconfiguration message from a first base station, wherein the RRC connection reconfiguration message comprises resource information of a cell of a second base station;

the UE sends an RRC connection reconfiguration complete message to the first base station;

the UE receiving a first portion of downlink data from the first base station that originates from the second base station;

the UE receives a second portion of the downlink data from the second base station over a Uu interface.

13. The method according to claim 12, wherein the method further comprises:

the UE sends a first part of uplink data to the second base station;

and the UE transmits a second part of the uplink data to the second base station through the first base station.

14. An apparatus for transmitting data, comprising:

Means for a first base station to send a request message to a second base station, the request message being for instructing the second base station to establish a data radio bearer, DRB, for a user equipment, UE, and further for instructing the second base station to act as a user plane anchor;

a unit for the first base station to receive a response message from the second base station, the response message carrying resource information of a cell of the second base station;

a unit for the first base station to send a radio resource control, RRC, connection reconfiguration message to the UE, the RRC connection reconfiguration message including resource information of a cell of the second base station;

a unit for the first base station to receive downlink data of the UE from the second base station;

and the unit is used for sending the downlink data to the UE by the first base station.

15. The apparatus of claim 14, wherein the apparatus further comprises:

a unit for the first base station to receive uplink data from the UE;

and the unit is used for sending the uplink data to the second base station by the first base station.

16. The apparatus according to claim 14 or 15, characterized in that the apparatus further comprises:

A unit for the first base station to receive a radio resource control RRC connection reconfiguration complete message sent by the UE;

and means for the first base station transmitting a configuration completion message to the second base station.

17. The apparatus according to claim 14 or 15, wherein the request message is further configured to instruct the second base station to establish a signaling radio bearer, SRB, for the UE.

18. The apparatus according to claim 14 or 15, characterized in that the apparatus further comprises:

and the unit is used for receiving a capacity allocation indication message sent by the second base station by the first base station, wherein the capacity allocation indication message is used for indicating the buffer information of the data distribution transmission between the second base station and the first base station.

19. The apparatus according to claim 14 or 15, characterized in that the apparatus further comprises:

the apparatus includes means for receiving an extended power headroom report, PHR, for the first base station, the extended PHR including a first type power headroom, PH, and a second type PH of a first cell of the first base station, and a first type PH and a second type PH of a second cell of the second base station.

20. An apparatus for transmitting data, comprising:

Means for receiving, by a second base station, a request message from a first base station, the request message for instructing the second base station to establish a data radio bearer, DRB, for a user equipment, UE, and for instructing the second base station to act as a user plane anchor;

a unit for the second base station to send a response message to the first base station, wherein the response message carries resource information of a cell of the second base station;

a unit for the second base station to receive downlink data of the UE from a core network device;

and the unit is used for shunting the downlink data by the second base station, sending the first part of the downlink data to the first base station, and sending the second part of the downlink data to the UE through a Uu interface.

21. The apparatus of claim 20, wherein the apparatus further comprises:

means for the second base station receiving a first portion of uplink data from the UE;

means for the second base station receiving a second portion of uplink data of the UE from the first base station;

and the unit is used for the second base station to send the first part of the uplink data and the second part of the uplink data to the core network equipment.

22. The apparatus according to claim 20 or 21, characterized in that the apparatus further comprises:

and means for the second base station receiving a configuration complete message from the first base station.

23. The apparatus according to claim 20 or 21, wherein the request message is further configured to instruct the second base station to establish a signaling radio bearer, SRB, for the UE.

24. The apparatus according to claim 20 or 21, characterized in that the apparatus further comprises:

and the unit is used for sending a capacity allocation indication message to the first base station by the second base station, wherein the capacity allocation indication message is used for indicating the buffer information of the data distribution transmission between the second base station and the first base station.

25. An apparatus for transmitting data, comprising:

means for a user equipment, UE, to receive a radio resource control, RRC, connection reconfiguration message from a first base station, the RRC connection reconfiguration message comprising resource information of a cell of a second base station;

means for the UE sending an RRC connection reconfiguration complete message to the first base station;

means for the UE to receive from the first base station a first portion of downlink data from the second base station;

And means for the UE receiving a second portion of the downlink data from the second base station over a Uu interface.

26. The apparatus of claim 25, wherein the apparatus further comprises:

a unit for the UE to send a first portion of uplink data to the second base station;

and means for the UE transmitting a second portion of the uplink data to the second base station through the first base station.

27. An apparatus for transmitting data, comprising at least one processor for executing a computer program stored in a memory, causing the apparatus to perform the method of any one of claims 1 to 6, or causing the apparatus to perform the method of any one of claims 7 to 11, or causing the apparatus to perform the method of claim 12 or 13.